Beta-amino carbonyl catalysts for polyurethane preparation

ABSTRACT

Provided as catalysts for the formation of cellular urethane polymers ranging from flexible to rigid foams, are beta-amino carbonyl compounds wherein carbonyl is present as an amido or carboxylic acid ester group and the beta-amino group is present as dialkylamino or an N-morpholino or N,N&#39;-piperazino heterocyclic nucleus. Effective in the catalysis of the water-isocyanate reaction, these beta-amino amides and beta-amino esters are used with particular advantage in the manufacture of water-blown flexible foams, both molded and free-rise, including high-resilience and flame-retarded foam. The beta-amino carbonyl catalysts allow for the formation of foam products essentially free of the odor associated with amines such as N-ethylmorpholine. In view of this highly desirable characteristic and their other beneficial properties, the catalysts of the invention are advantageously employed as direct replacements for N-ethylmorpholine in high-resilience and other foam formulations.

This is a division of application Ser. No. 463,247, filed Apr. 23, 1974,now U.S. Pat. No. 3,954,749 granted May 4, 1976. This latter applicationwas filed under Rule 60 and in turn is a division of application Ser.No. 309,906, filed Nov. 27, 1972, now U.S. Pat. No. 3,821,131, grantedJune 28, 1974.

BACKGROUND OF THE INVENTION

This invention pertains to particular betaamino carbonyl compounds ascatalysts for the formation of urethane polymers by the reaction oforganic isocyanates with active hydrogen-containing compounds.

It is well known to the art that urethane polymers are provided by thereaction of organic polyisocyanates and active hydrogen-containingorganic compounds, usually in the presence of one or more activators,and that blowing action is provided when cellular products includingflexible, semi-flexible and rigid foams, are desired. It is also knownthat a number of different chemical reactions occur during polymerformation and expansion. For example, in addition to the chainextending,urethane-forming reaction between free isocyanate groups and activehydrogen, initially formed urethane linkages bearing secondary hydrogenmay also function as a source of active hydrogen and react withadditional isocyanate to form cross-links between polymer chains.Further, in water-containing systems such as those employed for themanufacture of flexible foams, isocyanate is also consumed by reactionwith water, thereby generating carbon dioxide blowing agent in situ, andintroducing further cross-links comprising urea groups. The nature ofthe cellular structure and the physical and mechanical properties of thefoam are influenced by the extent of such reactions, and the relativerates and point in time at which they occur. Although balancing thesevariables so as to achieve a particular type or grade of foam can becontrolled to some extent by the functionality, molecular weight andother structural features of the polyisocyanate and activehydrogencontaining reactants, the catalyst system also plays asignificant role in this respect.

Among the relatively few compounds that have achieved widespreadcommercial application as catalysts in polyurethane manufacture are:tertiary amines consisting of carbon, hydrogen and nitrogen, astypically illustrated by 1,4-diazabicyclo[2.2.2]octane("triethylenediamine") and N,N,N',N'-tetramethyl-1,3-butanediamine; andtertiary amines consisting of carbon, hydrogen, nitrogen and oxygenwherein oxygen is present as ether oxygen, as typically illustrated bybis[2-(N,N-dimethylamino)ethyl]ether and N-ethylmorpholine. Withparticular reference to the manufacture of flexible polyetherpolyol-based urethane foams, such tertiary amines are usually employedin combination with auxiliary catalysts comprising organic derivativesof tin such as stannous octoate and dibutyltin dilaurate, in order toprovide a synergistic activation of the chain-extending reaction.

A relatively recent advance in the area of flexible polyurethane foamtechnology which has triggered intensive research effort to developimproved activators, is the advent of reaction mixtures having asufficiently high reactivity to provide more complete reactions duringpolymer formation and expansion, thereby eliminating the need incommercial practice to post-cure the foam at high temperatures(300°-500° F.) to obtain a product of satisfactory overall properties.In addition to the saving in cost which elimination of high temperaturepost-curing offers to the foam manufacturer, such highly reactiveformulations also provide flexible foams of generally improvedflammability characteristics, more linear and thus improvedload/deflection properties, low flex fatigue, and greater resiliency. Inview of this latter characteristic, such products are referred togenerally as high-resilience foams. In view of the aforesaid combinationof properties, high-resilience foam is particularly suited as cushioningmaterial in automotive interiors. In the production of at least asubstantial proportion of high-resilience foam being manufactured at thepresent time, the aforementioned N-ethylmorpholine is used as a majorcomponent of mixed catalyst systems. However the usefulness ofN-ethylmorpholine in the manufacture of high-resilience foam as well asother types of cellular urethanes, is attended with certaindisadvantages. Thus, N-ethylmorpholine suffers the very serious drawbackof having a particularly strong amine odor. The large quantities ofN-ethylmorpholine which are employed relative to other catalystcomponents of the foam formulation, causes an obnoxious atmosphere atand surrounding the foam manufacturing plant site and also providesfoams having a strong residual amine odor. This compound is alsoassociated with a number of serious toxic effects; see, for example,Plastics Technology, "Catalysts Improve As Their Need Increases" pages47-49 (July 1972). Consequently, it is desirable and is a primaryobjective of this invention to find a direct replacement forN-ethylmorpholine in the production of high-resilience foam inparticular and cellular urethane manufacture generally and thereby allowfor at least a substantial reduction in the relatively large amountspresently employed. Various other objects and advantages of the presentinvention will become apparent from the accompanying description anddisclosure.

SUMMARY OF THE INVENTION

In accordance with the teachings of the present invention, cellularpolyurethanes are provided by effecting reaction of activehydrogen-containing compounds and polyisocyanates in the presence of aparticular class of betaamino carbonyl compounds as catalytic componentsof the urethane-forming reaction mixture. The catalysts employed in thepractice of this invention consist of carbon-bonded nitrogen, oxygen andhydrogen atoms and contain at least one tertiary nitrogen atom bonded toa carbon atom beta to the carbonyl group of an amido or carboxylic acidester group. Tertiary nitrogen of the essential beta-amino carbonylgroup is present in the molecule as a dialkylamino group or as a memberof an N-heterocyclic nucleus which may contain additional hetero atomssuch as oxygen or a second ntrogen atom. Overall, the beta-aminocarbonyl compounds employed as described herein contain from 6 to 46carbon atoms, from 1 to 4 nitrogen atoms and from 1 to 4 oxygen atoms.Except for carbonyl oxygen, the remaining atoms are joined throughsingle bonds and thus the catalysts employed in the practice of thisinvention are free of multiple bonds between adjacent carbon atoms andadjacent carbon and nitrogen atoms.

The aforesaid essential structural characteristics of the beta-aminoamides and beta-amino esters employed as described herein areconveniently expressed by the following general Formula I: ##STR1##wherein, and as defined for the purpose of the entire specification:

Y is an oxygen or nitrogen atom and, when Y is nitrogen, the remainingvalence thereof is satisfied by a bond to a second --CH(R₃)CH(R₄)C(O)Qgroup;

p and q each has a value of zero or one, provided the sum p+q is one;

m is an integer having a value from 1 to 4, provided m is two when q isone;

R₃ and R₄ each represents hydrogen or a lower alkyl group and may be thesame as or different from one another; and

Q is a member of the group consisting of an alkoxy group (--OR₇) havingfrom 1 to 8 carbon atoms, an N,N-dialkylamino group, --N(R₅)(R₆), whereR₅ and R₆ each represents a lower alkyl group, or a2-(N,N-dialkylamino)ethoxy group, --OCH₂ CH₂ N(R₅)(R₆), where R₅ and R₆also represent lower alkyl radicals.

It is to be understood that the expression "lower alkyl" as used hereinincluding the claims, denotes an alkyl radical having from one to fourcarbon atoms including linear and branched radicals (that is, radicalsof the series, C_(m) H_(2m) _(+p), wherein m is an integer from 1 to 4and p is one).

It has been discovered that the above-described beta-amino carbonylcompounds are useful as catalytic components in the manufacture of awide variety of cellular urethanes including products ranging fromflexible to rigid foams. They are effective activators when used as thesole nitrogen-bearing catalytic component of foam formulations, althoughtheir employment in combination with other tertiary amines is within thescope of the present invention. Especially effective in the catalysis ofthe water-isocyanate reaction, these beta-amino amides and esters areused with particular advantage in the manufacture of water-blownflexible foams, both molded and free-rise, including high-resiliencefoam. In addition to their versatility in this respect, they have thefurther highly desirable characteristic of low residual odor and thusallow for the formation of foam products essentially free of thepost-cure odor associated with N-ethylmorpholine. Other beneficialproperties include excellent mold-release characteristics, wideformulating latitude with respect to concentration of tin co-catalysts,and ability to provide open-cell, porous foam from formulationscontaining an added flame-retarding agent.

It is noted that, as a class, beta-amino amides and esters includingspecific compounds employed in the practice of this invention arereported in the literature. As far as is known, however, their abilityto function as catalysts in cellular urethane polymer formation has notbeen previously reported. On the other hand, certain of the beta-aminocarbonyl compounds employed as catalysts in the practice of thisinvention are novel compositions. These include: (1) the heterocyclicbeta-amino amides encompassed by Formula I, that is, these compounds inwhich q is one and Q is an N,N-dialkylamino group; (2)3-dialkylamino-N,N-dialkylamides wherein the alkyl groups bonded toamino nitrogen are different from those bonded to amido nitrogen; and(3) 3-dialkylamino-3-alkyl-N,N-dialkylamides wherein the various alkylgroups may be the same as or different from one another.

The present invention also relates to particular blends of thebeta-amino carbonyl catalysts encompassed by Formula I with othertertiary amines, the use of such blends as mixed amine catalyst systemsfor cellular polyurethane formation, and to the cellular urethanepolymers produced in the presence of the catalysts described herein.

DETAILED DESCRIPTION OF THE INVENTION AND PREFERRED EMBODIMENTS

A. The Beta-Amino Carbonyl Catalysts

In generic Formula I, the sum p+q is one and thus when q is zero, p musthave a value of one. In the latter event, each C_(m) H_(2m) _(+p) groupshown in Formula I is a lower alkyl radical, designated herein as R₁ andR₂, and the indicated valence of carbon which would otherwise be inassociation with Y is satisfied by the additional hydrogen atom presentwhen p is one. The resulting saturated, acyclic beta-amino esters andamides have the more specific Formula II: ##STR2## When Q is an alkoxygroup, the catalysts encompassed by Formula II are alkyl beta-(dialkylamino)carboxylates having the following Formula II-A: ##STR3##When Q of Formula II is a 2-(N,N-dialkylamino)ethoxy group, thecatalysts are 2-(N,N-dialkylamino)ethyl3-(N',N'-dialkylamino)carboxylates having the following Formula II-B:##STR4## Further, when Q is an N,N-dialkylamino group, the catalystsencompassed by Formula II, are beta-(dialkylamino)-N,N-dialkylamides andhave the structure shown by the following Formula II-C: ##STR5##

In addition to the saturated, acyclic esters and amides shownspecifically by Formulas II-A, II-B and II-C, general Formula I alsoencompasses compounds wherein tertiary nitrogen is a member of amorpholine or piperazine nucleus. Such catalysts for use in the practiceof this invention are depicted by the following Formulas III and IV,respectively: ##STR6## wherein the --C(O)Q group may be present as theester groups shown in Formulas II-A and II-B or the amido group shown inFormula II-C. For example, when the Q radical of Formulas III and IV isa dialkylamino group, the respective compounds are3-(N-morpholino)-N',N'-dialkylamides andN,N'-piperazinobis[3-(N",N"-dialkylamides)]. These heterocyclicbeta-amino amide catalysts are novel compounds and have the followingmore specific Formulas III-A and IV-A, respectively: ##STR7##

In the above formulas and as shown elsewhere in the presentspecification, R₁, R₂, R₅ and R₆ represent lower alkyl radicals, R₃ andR₄ may be hydrogen or lower alkyl, and R₇ represents an alkyl radicalhaving from 1 to 8 carbon atoms including linear and branched radicalsand is more usually lower alkyl. It is to be understood that the loweralkyls represented by R₁, R₂, R₅ and R₆ and encompassed by R₃, R₄ andR₇, may be the same as or different from one another. The generallypreferred catalysts for use in the practice of the present invention arethose compounds wherein R₁, R₂, R₅ and R₆ are methyl or ethyl includingany combination thereof and wherein at least one of R₃ and R₄ ishydrogen and the other is either hydrogen, methyl or ethyl.

In addition to the heterocyclic beta-amino amides encompassed byFormulas III-A and IV-A, particular acyclic compounds defined by FormulaII-C are also novel compounds. Thus, when in Formula II-C, the alkylgroups represented by R₁ and R₂ are different from those represented byR₅ and R₆, the resulting unsymmetrically N-substituted3dialkylamino-N,N-dialkylamides are new compositions including thosewherein R₃ and R₄ are hydrogen or alkyl, as previously defined. Alsonovel are the 3-dialkylamino3-alkyl-N,N-dialkylamides, that is, thosecompounds encompassed by Formula II-C in which R₃ is limited to an alkylgroup and R₁, R₂, R₄, R₅ and R₆ are as previously defined.

As between the various types of compounds employed in the practice ofthis invention, the catalysts encompassed by Formulas II and III aregenerally preferred in that they also offer the processing advantage ofbeing normally liquid materials, whereas the piperazine derivedcatalysts (Formula IV) are solids. From this standpoint, the acycliccatalysts having Formula II are especially preferred in that they aregenerally less viscous than the morpholine derivatives and thus can behandled and pumped more readily without dilution.

Typical examples of suitable catalysts for use in the formation ofcellular urethane polymers in accordance with the teachings of thisinvention are the following compounds which, for clarity, are groupedaccording to the structural formulas within which they specificallyfall, all such catalysts being within the scope of generic Formula I.

Formula II-A

methyl 3-(N,N-dimethylamino)propionate;

ethyl 3-(N,N-dimethylamino)propionate;

ethyl 3-(N,N-diethylamino)propionate;

n-butyl 3-(N,N-diethylamino)propionate;

i-butyl 3-(N,N-dimethylamino)butyrate;

2-ethylhexyl 3-(N,N-dimethylamino)propionate;

ethyl 2-methyl-3-(N,N-dimethylamino)propionate;

propyl 3-(N,N-diethylamino)hexanoate;

ethyl 3-(N-methyl-N-ethylamino)propionate; and

methyl 3-butyl-3-(N,N-dimethylamino)heptanoate.

Formula II-B

2-(n,n-dimethylamino)ethyl 3-(N',N'-dimethylamino)propionate;

2-(N,N-diethylamino)ethyl 3-(N',N'-diethylamino)propionate;

2-(N,N-diethylamino)ethyl 3-(N',N'-dimethylamino)propionate;

2-(N,N-dimethylamino)ethyl 2-methyl-3-(N',N'-dimethylamino)propionate;

2-(N-methyl-N-ethylamino)ethyl 3-(N',N'-dimethylamino)propionate; and

2-(N,N-diethylamino)ethyl 3-N'-methyl-N'-ethylamino)butyrate.

Formula II-C

3-dimethylamino-N,N-dimethylpropionamide;

3-diethylamino-N,N-dimethylpropionamide;

3-diethylamino-N,N-diethylpropionamide;

3-dimethylamino-N,N-di-n-propylpropionamide;

3-diethylamino-N,N-di-s-butylpropionamide;

3-(N-methyl-N-ethylamino)-N'-n-butyl-N'-methylpropionamide;

3-dimethylamino-2-methyl-N,N-dimethylpropionamide;

3-dimethylamino-N,N-dimethylbutyramide;

3-dimethylamino-N,N-dimethylpentamide; and

3-diethylamino-N,N-dimethylhexamide.

Formula III including Formula III-A

methyl 3-(N-morpholino)propionate;

ethyl-3-(N-morpholino)propionate;

ethyl 2-methyl-3-(N-morpholino)propionate;

methyl 3-(N-morpholino)butyrate;

2-(N,N-dimethylamino)ethyl 3-(N'-morpholino)propionate;

3-(N-morpholino)-N',N'-dimethylpropionamide;

3-(N-morpholino)-2-methyl-N',N'-dimethylpropionamide; and3-(N-morpholino)-N',N'-dimethylbutyramide.

Formula IV including Formula IV-A

dimethyl 3-(N,N'-piperazino)dipropionate;

diethyl 3-(N,N'-piperazino)dipropionate;

di-2-(N,N-dimethylamino)ethyl 3-(N',N"-piperazino)dipropionate; and

N,n'-piperazino-bis[3-(N",N"-dimethylpropionamide)].

The above-described beta-amino carbonyl compounds employed as catalystsin accordance with the present invention are readily prepared by anumber of different types of reactions. A particularly facile methodcomprises the reaction of (A) secondary amines and (B) ester or amidoderivatives of alpha,beta- unsaturated carboxylic acids. With specificreference to Formula I, the overall reaction by which such compounds areprovided is as follows: ##STR8## Consistent with the structure of thecompounds encompassed by Formula I, Reactant A may be: adi(lower)alkylamine [(R₁)(R₂)NH] as typically illustrated bydimethylamine, diethylamine, di-n-propylamine, di-i-propylamine,dibutylamine, methylethylamine; or the heterocyclic amines, morpholineand piperazine. Also with reference to the structure of the compoundsencompassed by Formula I, Reactant B may be: an alkyl (R₇) or a2-(N,N-dialkylamino)ethyl [--CH₂ CH₂ N(R₅)(R₆)] ester derivative of analpha,beta-unsaturated carboxylic acid having the formula,CH(R₃)=C(R₄)C(R₄)C(O)OH; or an alpha,betaunsaturatedN,N-di(lower)alkylamide having the formula, CH(R₃)=C(R₄)C(O)N(R₅)(R₆).Typical examples of suitable unsaturated esters included within thedefinition of Reactant B are: methyl, ethyl, n-propyl, n-butyl, i-butyl,2-ethylhexyl, 2-(N,N-dimethylamino)ethyl, 2-(N,N-diethylamino)ethyl and2-(N-methyl-N-ethylamino)ethyl ester derivatives of acrylic,methacrylic, crotonic, 2-methylcrotonic (tiglic), 2-ethylpropenoic,2-pentenoic, 2-ethyl-2-pentenoic, 2-hexenoic and 2-heptenoic acids.Illustrative of suitable unsaturated amide reactants encompassed by thedefinition of Reactant B are the corresponding amides containing theCH(R₃)=C(R₄)C(O)-nucleus of the aforesaid acids such asN,N-dimethylacrylamide, N,N-diethylacrylamide,N-methyl-N-ethylacrylamide, N,N-dimethylmethacrylamide, andN,N-dimethylcrotonamide.

Encompassed by the overall reaction of equation (1) is the direct 1:1addition of the reactive H--N> group (or groups as in piperazine) ofReactant A across the double bond of Reactant B to form thecorresponding beta-amino ester and amide adducts, as illustrated by thefollowing equations (2)-(6): ##STR9##

It is to be understood that replacement of the ester reactant shown inequation (5) with the unsaturated ester reactant shown in equation (3),provides the corresponding 2-(N,N-dialkylamino)ethyl3-(N'-morpholino)-carboxylates, such compounds, as well as the esterproducts of equation (5), being encompassed by Formula III. It also isto be understood that when morpholine is reacted with the unsaturatedamide reactants shown in equation (4), the products are thecorresponding 3-(N-morpholino)-N',N'-dialkylamides which are alsoencompassed by Formula III and defined specifically by Formula III-A.Similarly, when the ester reactant shown in equation (6) is replacedwith the unsaturated ester reactant shown in equation (3), thecorresponding di-2-(N,N-dialkylamino)ethyl3-(N',N"-piperazino)dicarboxylates are provided, such products as wellas those of equation (6) being encompassed by Formula IV. Likewise,reaction of 1,4-piperazine with the alpha,beta-unsaturated amides shownin equation (4) provides the correspondingN,N'-piperazino-bis[3-(N",N"-dialkylamides)] which are also encompassedby Formula IV and defined specifically by Formula IV-A.

The addition reactions illustrated by equations (2)-14 (6) are effectedat temperatures within the range from about minus 15° C. to about 120°C. and proceed at satisfactory rates at ambient or substantiallyatmospheric pressures. Reactions based on dimethylamine are generallymore highly exothermic than those based on higher homologues and thusare usually effected at the lower temperatures within the aforesaidrange. As required, temperature control is achieved in conventionalmanner such as by cooling or appropriate adjustment of the rate at whichthe reactants are fed to the reactor. The relative proportions ofreactants are such to at least satisfy the indicated stoichiometricrequirements of the addition, although either reactant may be employedin excess of stoichiometry to favor completion of the reactions.Usually, no more than a 125 percent molar excess of either reactant isemployed.

As illustrated by the reaction of equation (4), the beta-amino amidecatalysts can be prepared by the addition of secondary amines toalpha,beta-unsaturated, N,N-dialkylamides. These catalysts can also beprovided by the following application of the overall reaction ofequation (1):

Equation 7 ##STR10##

This reaction may be viewed as an extension of the addition reaction ofequation (2) in that it proceeds through intermediate formation of thealkyl beta(dialkylamino)carboxylates (Formula II-A) followed byamidation which is an endothermic reaction. Thus, for any givencombination of dialkylamine and alkyl alpha,beta-unsaturated carboxylatereactants, higher severity conditions are employed when it is desired torecover the amidated product. Generally, the amidation reactionsencompassed by equation (7) are effected at temperatures within therange from about 100° C. to about 250° C. and at elevated pressures fromabout 50 to 1200 p.s.i.g. In order to favor completion of the reaction,the amine reactant is preferably employed in excess of stoichiometry,amounts up to about a 100 percent molar excess usually being suitablefor this purpose. The reaction of equation (7) may be carried out inbatchwise fashion by initially charging total reactants to the reactorand applying the aforesaid high temperature-elevated pressureconditions. Alternatively, the reaction may be carried out as anessentially two-stage process. In accordance with the latter method, aportion of total amine reactant is fed to the unsaturated ester underthe less severe addition reaction conditions to form the 1:1 adduct,followed by reaction of the intermediate with the remainder of amineunder the aforesaid more severe amidation conditions. It is to beunderstood that the amine fed to the first stage may be different fromthat fed to the second stage, thereby providing amino and amido groupshaving a different combination of R₁ and R₂ groups, that is, compoundsencompassed by Formula II-C wherein the alkyl groups represented by R₁and R₂ are different from the alkyls represented by R₅ and R₆.

In order to minimize formation of by-products by retro-additionreactions and hydrolysis of ester reactants as well as ester products,it is recommended practice to effect the above-described reactions underanhydrous or substantially anhydrous conditions. Thus, the reactionmedia should contain less than about 5 weight per cent water, expressedon the basis of amine reactant. Formation of by-products such asalpha,betaunsaturated amides may also be formed during the reactions.Minor amounts of compounds which have an inhibiting effect onpolymerization of such by-products may be added to the reaction media.Illustrative of suitable inhibitors are phenothiazine, p-methoxyphenoland hydroquinone. The reaction media may also contain solvents ordiluents such as, for example, ethanol, butanol, diisopropyl ether,dioxane and other such compounds which are inert under the reactionconditions.

The technique by which the beta-amino amide and ester catalysts arerecovered depends largely on their physical nature and properties. Thus,the normally liquid products encompassed by Formulas II and III arerecovered by distillation or as residue products remaining after removalof more volatile components. Recovery as residue products is usualpractice in the case of the higher molecular weight compounds such asthe morpholinederived compounds and acyclic compounds in which thevarious alkyl groups are propyl and butyl. The piperazinederivedcatalysts are recovered by conventional liquid-solid separationtechniques.

The effectiveness of the beta-amino carbonyl compounds as catalysts forcellular urethane manufacture as described herein, does not depend ontheir use in a rigorously pure state. Included within the scope of thepresent invention, therefore, is the use of the catalysts as eithersubstantially pure compounds, in combination with one another, or inassociation with impurities which may form during their manufacture.

(B) THE FOAM FORMULATIONS

In producing cellular urethane polymers in accordance with the teachingsof this invention, the reaction mixture or foam formulation contains, inaddition to the beta-amino carbonyl catalysts, an organic polyisocyanateand an active hydrogen-containing organic compound having an average ofat least two and usually not more than eight active hydrogen atomspresent as hydroxyl groups. Such organic polyol reactants includecompounds consisting of carbon, hydrogen and oxygen as well as compoundswhich contain these elements in combination with phosphorus, halogenand/or nitrogen. Suitable classes of organic polyol reactants for use inthe method of this invention are polyether polyols, polyester polyols,polylactone polyols, nitrogen-containing polyols, phosphorus-containingpolyols, phenolic-based polyols, and polymer/polyols produced bypolymerizing an ethylenically unsaturated monomer in one of theaforesaid polyols in the presence of a free radial initiator.

It is well known to the polyurethane art that the particular polyolreactant or combination of polyols employed depends upon the end-use ofthe polyurethane product which in turn determines whether the product isto be provided as a flexible, semi-flexible or rigid material. For thispurpose, the polyol reactant is usually characterized by its hydroxylnumber which is determined by and defined as the number of milligrams ofpotassium hydroxide required for the complete neutralization of thehydrolysis product of the fully acetylated derivative prepared from 1gram of polyol or mixture of polyols. The hydroxyl number is alsodefined by the following equation which reflects its relationship withthe functionality and molecular weight of the polyol reactant: ##EQU1##wherein OH = hydroxyl number of the polyol;

f = average functionality, that is, average number of hydroxyl groupsper molecule of polyol; and

M. w. = average molecular weight of the polyol.

The beta-amino carbonyl compounds described herein are suitably employedas catalytic components of foam formulations containing polyols havinghydroxyl numbers from about 20 to about 1000. In producing flexiblefoams, polyols having relatively low hydroxyl numbers such as from about20 to about 100 are generally employed. In producing semi-flexiblematerials, the hydroxyl number is usually from about 100 to about 300.Polyols having relatively high hydroxyl numbers of from about 300 toabout 1000 are used in rigid foam formulations.

Suitable polyethers that can be employed include linear and branchedpolyethers preferably having a plurality of ether linkages andcontaining at least two hydroxyl groups and being substantially freefrom functional groups other than hydroxyl. For convenience, this classof polyether polyols are referred to herein as Polyol I. These compoundsinclude alkylene oxide adducts of water such as polyethylene glycolshaving average molecular weights from about 200 to about 600,polypropylene glycols having average molecular weights from about 400 toabout 2000, and polyoxyalkylene polyols having a combination ofdifferent alkylene oxide units. Other suitable polyols encompassedwithin the definition of Polyol I are the alkylene oxide adducts ofpolyhydric organic initiators, the nature of which determines theaverage hydroxyl functionality of the polyoxyalkylated product.Illustrative of suitable polyhydric organic initiators are the followingwhich can be employed individually or in combination with one another:(1) diols such as ethylene glycol, diethylene glycol, propylene glycol,1,5-pentanediol, hexylene glycol, dipropylene glycol, trimethyleneglycol, 1,2-cyclohexanediol, 3-cyclohexene-1,1-dimethanol and3,4-dibromocyclohexane-1,1-dimethanol; (2) triols such as glycerol,1,2,6-hexanetriol, 1,1,1-trimethylolethane, 1,1,1-trimethylolpropane,3-(2-hydroxyethoxy)- and 3-(2-hydroxypropoxy)-1,2-propanediols,2,4-dimethyl-2-(2-hydroxyethoxy)methyl-pentanediol-1,5,1,1,1-tris[(2-hydroxyethoxy)methyl]ethane and1,1,1-tris[(2-hydroxypropoxy)methyl]propane; (3) tetrols such aspentaerythritol; (4) pentols, hexols, heptanols and octanols such asglucose, sorbitol, bis(2,2,2-trimethylol)ethyl ether, alpha-methylglucoside, sucrose, mannose and galactose; (5) compounds in whichhydroxyl groups are bonded to an aromatic nucleus such as resorcinol,pyrogallol, phloroglucinol, di-, tri- and tetra-phenylol compounds suchas bis(p-hydroxyphenyl)-methane and 2,2-bis(p-hydroxyphenyl)propane; and(6) alkylene oxide adducts of the aforesaid initiators such as propyleneor ethylene oxide adducts of glycerol having a relatively low averagemolecular weight up to about 600. Particularly useful in the preparationof flexible foams generally are polyether polyols having an averagehydroxyl functionality of from about 2.1 to about 4. Such polyols areprovided by the employment of either trihydric or tetrahydric starters,mixtures thereof, or appropriate mixtures containing diol starters. Themore highly functional polyether polyols are usually employed inproviding the semi-flexible and rigid foams.

The above-described polyether polyols are normally liquid materials and,in general, are prepared in accordance with well known techniquescomprising the reaction of the polyhydric starter and an alkylene oxidein the presence of an oxyalkylation catalyst. Usually, the catalyst isan alkali metal hydroxide such as, in particular, potassium hydroxide.The oxyalkylation of the polyhydric initiator is carried out attemperatures ranging from about 90° C. to about 150° C. and usually atan elevated pressure up to about 200 p.s.i.g., employing a sufficientamount of alkylene oxide and adequate reaction time to obtain a polyolof desired molecular weight which is conveniently followed during thecourse of the reaction by standard hydroxyl number determinations, asdefined above. The alkylene oxides most commonly employed in providingthe reactants encompassed by Polyol I, are the lower alkylene oxides,that is, compounds having from 2 to 4 carbon atoms including ethyleneoxide, propylene oxide, butylene oxides (1,2- or 2,3-) and combinationsthereof. When more than one type of oxyalkylene unit is desired in thepolyol product, the alkylene oxide reactants may be fed to the reactionsystem sequentially to provide polyoxyalkylene chains containingrespective blocks of different oxyalkylene units or they may be fedsimultaneously to provide substantially random distribution of units.Alternatively, the polyoxyalkylene chains may consist essentially of onetype of oxyalkylene unit such as oxypropylene capped with oxyethyleneunits.

A second class of polyols that are suitable for use in preparingpolyurethane foams in accordance with the present invention arepolymer/polyols which, for convenience, are referred to herein as PolyolII. Such reactants are produced by polymerizing one or moreethylenically unsaturated monomers dissolved or dispersed in any of theother types of organic polyol reactants described herein, in thepresence of a free radical catalyst. Especially suitable as thesubstrate polyols for producing such compositions are any of theabove-described polyether polyols encompassed by the definition ofPolyol I. Illustrative of suitable ethylenically unsaturated monomersare vinyl compounds having the general formula, ##STR11## where: R° ishydrogen, methyl or any of the halogens (i.e., fluorine, chlorine,bromine or iodine); and R°° is R°, cyano, phenyl, methyl-substitutedphenyl, carboalkoxy, or alkenyl radicals having from 2 to 6 carbon atomssuch as vinyl, allyl and isopropenyl groups. Typical examples of suchpolymerizable monomers are the following which may be employedindividually or in combination: ethylene, propylene, acrylonitrile,methacrylonitrile, vinyl chloride, vinylidene chloride, styrene,alpha-methylstyrene, methyl methacrylate, and butadiene. These and otherpolymer/polyol compositions which are suitably employed eitherindividually or in combination with Polyol I are those described inBritish Pat. No. 1,063,222 and U.S. Pat. Nos. 3,304,273, 3,523,093 and3,383,351, the disclosures of which are incorporated herein byreference. Such compositions are prepared by polymerizing the monomersin the polyol at a temperature between about 40° C. and about 150° C.employing any free radical-generating initiator including peroxides,persulfates, percarbonates, perborates and azo compounds. Illustrativeof suitable initiators are: hydrogen peroxide, dibenzoyl peroxide,benzoyl hydroperoxide, lauroyl peroxide and azobis(isobutyronitrile).

The polymer/polyol compositions usually contain from about 5 to about50, and more usually from about 10 to about 40, weight percent of thevinyl monomer or monomers polymerized in the polyol. Especiallyeffective polymer/polyols are those having the following composition:

(A) from about 10 to about 30 weight per cent of a copolymer of (1)acrylonitrile or methacrylonitrile, and (2) styrene oralpha-methylstyrene, the said copolymer containing from about 50 to 75and from about 50 to 25 weight per cent of monomeric units of (1) and(2), respectively; and

(B) from about 90 to about 70 weight per cent of one or more of thepolyols encompassed by Polyol I as the medium in which said component(A) is polymerized, the trifunctional polyols such as alkylene oxideadducts of glycerol being especially suitable. These polymer/polyolcompositions containing components (A) and (B) are the subject ofcopending U.S. application Ser. No. 176,317, filed Aug. 30, 1971, in thename of David C. Priest, now abandoned.

Other types of suitable polyol reactants for use in producing cellularpolyurethanes as described herein are polyester polyols provided as thereaction products of: (1) a polyfunctional organic carboxylic acid, and(2) one or more of the aforesaid polyether polyols or one or more of theaforesaid polyhydric organic compounds which are reacted with alkyleneoxide to produce such polyether polyols. Among the suitablepolycarboxylic acids that can be employed in producing such polyesterpolyols are: the aliphatic acids which are usually free of reactiveunsaturation such as ethylenic and acetylenic groups, such as, forexample, succinic acid, adipic acid, sebacic acid, azelaic acid,glutaric acid, pimelic, malonic, and suberic acids; cycloaliphatic acidssuch as chlorendic acid; and aromatic poly-basic acids such as phthalic,terephthalic, isophthalic acids and the like.

Also contemplated for use as a polyol reactant of the foam formulationsemployed in the practice of this invention are nitrogen-containingpolyols. Such polyols include lower alkylene oxide adducts of thefollowing amines which may be employed individually or in combination:primary and secondary polyamines such as ethylenediamine,diethylenetriamine and toluenediamine; and aminoalkanols such asethanolamine, diethanolamine, triethanolamine and triisopropanolamine.Also suitable are mixed starters containing one or more of the aforesaidpolyfunctional amines, aniline, and/or one or more of the polyhydricinitiators employed to produce Polyol I such as dipropylene glycol,glycerol and sucrose. Also illustrative of suitable nitrogen-containingpolyols are aniline/formaldehyde and aniline/phenol/formaldehydecondensation products. Such amine-based polyols are usually employed inrigid foam formulations.

Other suitable polyols for use in producing polyurethane foams asdescribed herein are: lactone-based polyols prepared by reacting alactone such as epsiloncaprolactone, or a mixture ofepsilon-caprolactone and an alkylene oxide, with a polyfunctionalinitiator such as a polyhydric alcohol, an amine, or an aminoalcohol;phosphorus-containing polyols such as the alkylene oxide adducts ofphosphoric acid, polyphosphoric acids such as tri- and tetra-phosphoricacids, organo-substituted phosphoric acids such as benzenephosphoricacid; and other polyol reactants known to the polyurethane art.

The beta-amino carbonyl compounds described herein are used withparticular advantage as catalysts in the manufacture of high-resilienceflexible foam. Such foams usually have a resiliency of from about 55 toabout 70 per cent, as measured by standard test procedure ASTMD-1564-69. In accordance with a preferred embodiment of this aspect ofthe present invention, the beta-amino carbonyl compounds are employed ascatalytic components of high-resilience foam formulations wherein atleast 40 weight per cent of the total polyol content is constituted of apolyether triol having the following additional characteristics: (a) anaverage primary hydroxyl content of at least 40 mole per cent (or nomore than 60 mole per cent of the less reactive secondary hydroxylgroups); and (b) an average molecular weight of from about 2000 to about8000. For convenience, this particular case of polyols are referred toherein as Polyol I-A. Preferably, such polyether triols for use ascomponents of high resilience formulations contain from about 60 toabout 90 mole per cent of primary hydroxyl groups and have an averagemolecular weight of from about 4000 to about 7000. Consistent with theirtrifunctionality and the aforesaid respective ranges of molecularweight, such polyether triols have hydroxyl numbers from 84 to 21,preferably from 42 to 24. These highly reactive polyether triols areprovided by oxyalkylation of one of the aforesaid trihydric starterssuch as glycerol, with propylene oxide and ethylene oxide. Usually, thetotal ethylene oxide content of the polyether triols encompassed by thedefinition of Polyol I-A is between about 7 and about 20 weight percent, expressed on the basis of total alkylene oxide fed during theoxyalkylation reaction. The high primary hydroxyl content is introducedby capping of the polyoxyalkylene chains with at least a portion of thetotal ethylene oxide feed.

In providing high-resilience foams, the polyether triols included withinthe definition of Polyol I-A may be used as essentially the sole type ofpolyol in the formulation or they may be employed in combination withother polyols to control the degree of softness or firmness of the foamand to vary the load-bearing properties. For example, when softer gradehigh-resilience foams are desired, Polyol I-A may be used in combinationwith polyether diols such as the above-described lower alkylene oxideadducts of a dihydric initiator such as dipropylene glycol. When firmgrades of high-resilience foams having enhanced load-bearing propertiesare desired, Polyol I-A is used in combination with up to about 60 partsby weight per 100 parts by weight of total polyol reactant (p.p.h.p.) ofa polymer/polyol encompassed within the definition of Polyol II. In thislatter respect, particularly effective mixtures of polyols are thosecontaining: (1) from about 40 to about 80 p.p.h.p. of the polyethertriols, designated hereinabove as Polyol I-A; and (2) from about 60 toabout 20 p.p.h.p. of polymer/polyols, designated herein as Polyol II-A,prepared by the in situ polymerization of a monomer mixture containingfrom about 50 to about 75 weight per cent of acrylonitrile and fromabout 50 to about 25 weight per cent of styrene, in Polyol I-A, the saidmonomer mixture constituting from about 10 to about 30 weight per centof the combined weight of the monomers and Polyol I-A. Thepolyisocyanates used in the manufacture of polyurethanes are known tothe art and any such reactants are suitably employed in producingpolyurethane foams in the presence of the beta-amino carbonyl catalystsdescribed herein. Among such suitable polyisocyanates are thoserepresented by the general formula:

    Q'(NCO).sub.i

wherein: i has an average value of at least two and is usually no morethan six, and Q' represents an aliphatic, cycloaliphatic or aromaticradical which can be an unsubstituted hydrocarbyl group or a hydrocarbylgroup substituted, for example, with halogen or alkoxy. For example,Q'can be an alkylene, cycloalkylene, arylene, alkyl-substitutedcycloalkylene, alkarylene or aralkylene radical including correspondinghalogen-and alkoxy-substituted radicals. Typical examples ofpolyisocyanates for use in preparing the polyurethanes of this inventionare any of the following including mixtures thereof: 1,6-hexamethylenediisocyanate, 1,4-tetramethylene diisocyanate,bis(2-isocyanatoethyl)fumarate, 1-methyl-2,4-diisocyanatocyclohexane,bis(4-isocyanatophenyl)methane, phenylene diisocyanates such as4-methoxy-1,4-phenylenediisocyanate, 4-chloro-1,3-phenylenediisocyanate,4-bromo-1,3-phenylenediisocyanate,5,6-dimethyl-1,3-phenylenediisocyanate, 2,4-tolylene diisocyanate,2,6-tolylene diisocyanate, crude tolylene diisocyanates,6-isopropyl-1,3-phenylenediisocyanate, durylene diisocyanate,triphenylmethane-4,4',4"-triisocyanate, and other organicpolyisocyanates known to the polyurethane art. Other suitablepolyisocyanate reactants are ethylphosphonic diisocyanate andphenylphosphonic diisocyanate. Of the aforesaid types ofpolyisocyanates, those containing aromatic nuclei are generallypreferred.

Also useful as the polyisocyanate reactant are polymeric isocyanateshaving units of the formula: ##STR12## wherein R'" is hydrogen and/orlower alkyl and j has an average value of at least 2.1. Usually, thelower alkyl radical is methyl and j has an average value no higher thanabout 4. Particularly useful polyisocyanates of this type are thepolyphenylmethylene polyisocyanates produced by phosgenation of thepolyamine obtained by acid-catalyzed condensation of aniline withformaldehyde. Polyphenylmethylene polyisocyanates of this type areavailable commercially under such trade names as PAPI, NIAX IsocyanateAFPI, Mondur MR, Isonate 390P, NCO-120, Thanate P-220, NCO-10 andNCO-20. These products are low viscosity (50-500 centipoises at 25° C.)liquids having average isocyanato functionalities in the range of about2.25 to about 3.2 or higher, and free --NCO contents of from about 25 toabout 35 weight per cent, depending upon the specificaniline-to-formaldehyde molar ratio used in the polyamine preparation.

Also useful as polyisocyanate reactants are polymeric tolylenediisocyanates obtained as residues from the manufacture of thediisocyanates and having a free --NCO content of from about 30 to about50 weight per cent, Other useful polyisocyanate reactants arecombinations of diisocyanates with polymeric isocyanates containing morethan two isocyanate groups per molecule. Illustrative of suchcombinations are: a mixture of 2,4-tolylene diisocyanate, 2,6-tolylenediisocyanate and the aforesaid polyphenylmethylene polyisocyanatesand/or the aforementioned residue products.

Of the aforesaid polyisocyanates, those employed with particularadvantage in providing high-resilience foams are mixtures containingfrom about 60 to about 90 weight per cent of the isomeric tolylenediisocyanates and from about 40 to about 10 weight per cent of thepolyphenylmethylene polyisocyanates, in order to enhance the average--NCO functionality and thus the reactivity of the reaction mixture.When the high-resilience formulations contain diisocyanates asessentially the sole source of reactive --NCO, it is often desirable toinclude minor amounts, such as up to about 1.5 p.p.h.p., ofcross-linking agents. Suitable additives for this purpose arediethanolamine, methyldiethanolamine and triethanolamine.

On a combined basis, the polyol reactant and organic polyisocyanateusually constitute the major proportion by weight of thepolyurethane-forming reaction mixture. In general, the polyisocyanateand polyol reactants are employed in relative amounts such that theratio of total --NCO equivalents to total active hydrogen equivalent (ofthe polyol and any water, when used) is from 0.8 to 1.5, usually from0.9 to 1.20, equivalents of --NCO per equivalent of active hydrogen.This ratio is known as the Isocyanate Index and is often also expressedas a per cent of the stoichiometric amount of polyisocyanate required toreact with total active hydrogen. When expressed as a percent, theIsocyanate Index may be from 80 to 150, and is usually within the rangefrom about 90 to about 120. More usually, the Isocyanate Index is nomore than about 115.

The beta-amino carbonyl catalysts may be employed individually or incombination with one another and are present in the foam formulation incatalytically effective amounts. Thus, the total concentration thereofmay vary over a relatively wide range such as from about 0.01 to about 5or more parts by weight (exclusive of any carrier solvents or otheradditives) per 100 parts by weight of the total polyol reactantcontained in the reaction mixture. Usually, this catalytic component ispresent in an amount from about 0.05 to about 3.0 p.p.h.p. In flexiblefoam formulations, it is usually adequate to employ the beta-aminocarbonyl catalysts in an amount up to about one p.p.h.p., whereas inrigid formulations, higher concentrations are usually used.

The beta-amino carbonyl catalysts may be employed as the sole type ofamine catalyst of the foam formulations described herein or they may beemployed in combination with one or more tertiary amines conventionallyemployed as catalysts in producing polyurethanes. Such additionalcatalysts include amines consisting of carbon, hydrogen and nitrogen, aswell as amines consisting of these three elements and oxygen whereinoxygen is present solely as ether or hydroxyl groups. Although theseauxiliary amine catalysts can contain up to 24 carbon atoms, the morecommonly employed compounds contain no more than 12 carbons.Illustrative of such tertiary amines for use in combination with thebeta-amino carbonyl catalysts are: trimethylamine; triethylamine;tributylamine; N,N,N',N'-tetramethylethylenediamine;N,N,N',N'-tetramethyl-1,3-butanediamine; N,N-dimethylcyclohexylamine;N,N-dimethylbenzylamine; bis[2-(N,N-dimethylamino)alkyl]ethers such asbis[2-(N,N-dimethylamino)ethyl]ether; triethylenediamine;N-methylmorpholine; N-ethylmorpholine; N-(2-hydroxyethyl)-piperazine;N-methyldiethanolamine; N,N-dimethylethanolamine; and other suchconventional tertiary amine polyurethane catalysts. Of the aforesaidtertiary amines, those containing reactive hydroxyl are often used toserve the additional function of cross-linking agents. Suchalkanolamines are often used in the manufacture of rigid foams, or toenhance cross-linking density of high-resilience foams based ondiisocyanates.

When used, the supplementary tertiary amine catalysts may be present inthe foam formulation in an amount within the aforesaid ranges definedwith respect to the beta-amino carbonyl catalysts, although usually thetotal amount of supplementary amine is no more than about one p.p.h.p.It is to be understood that the beta-amino carbonyl catalyst and thesupplementary tertiary amine, when used, may be added to the formulationas separate streams or in preblended form.

Illustrative of suitable blended catalysts provided by the presentinvention and which are especially useful as components of water-blown,flexible foam formulations including high-resilience systems, are thosecontaining from about 10 to about 90 weight per cent of the beta-aminocarbonyl compounds and correspondingly from about 90 to about 10 weightper cent of either bis[2-(N,N-dimethylamino)ethyl]ether,triethylenediamine, or the bis-amino ether plus triethylenediamine. Itis to be understood that the said weight percentages are based on thetotal weight of the blended catalysts, exclusive of carrier solvents orother additives. These blends are added to the foam formulations in anamount sufficient to provide the beta-amino carbonyl catalyst andauxiliary amine within the aforesaid respective ranges of concentration,that is, between about 0.01 and about 5 p.p.h.p.

From the standpoint of providing an effective catalyst system, thebeta-amino carbonyl catalyst may be used, as included in the foregoingdescription, in combination with N-alkylmorpholines such asN-ethylmorpholine. The latter compound is presently used in commercialpractice in relatively high concentrations (up to about 2.0 p.p.h.p.) asa catalytic component of molded high-resilience formulations in order toprovide foams having good mold-release characteristics. In view of thepresent discovery that such foams can be produced by employing thebeta-amino carbonyl catalysts described herein without the necessity ofusing N-ethylmorpholine, the latter catalyst may be completelyeliminated, thereby avoiding the obnoxious residual foam odor associatedtherewith. It is to be understood, however, that N-ethylmorpholine maybe used as a component of the foam formulations described herein withoutdeparting from the scope of this invention. When used, the level of suchN-alkylmorpholine catalysts is desirably kept to a minimum such as nomore than about 0.30 p.p.h.p.

It is to be understood that the beta-amino carbonyl catalysts employedin accordance with the present invention, as well as blends basedthereon, may be introduced to the foam formulations in undiluted form oras solutions in suitable carrier solvents such as diethylene glycol,dipropylene glycol and hexylene glycol. The supplementary aminecatalysts are also often employed in such carrier solvents.

Other useful carrier solvents for the catalysts described herein arelower alkylene oxide adducts of monohydric or polyhydric starters suchas butanol, dipropylene glycol and glycerol. Such solvents (or diluents)generally include adducts containing from about 3 to about 30oxyethylene or oxypropylene units, mixtures of such adducts, as well asadducts provided by reaction of the starter with ethylene oxide andpropylene oxide, fed either as a mixed feed or sequentially. Among thesuitable organic carrier solvents of this type are the ethyleneoxide-propylene oxide adducts of butanol having the average formula, C₄H₉ (OC₃ H₆)_(u) (OC₂ H₄)_(s) OH, wherein s and u may each have anaverage value from about 3 to about 30. Preferably, the values of s andu are such that the average molecular weight of these fluids is notsubstantially greater than about 2000 and the oxyethylene content isfrom about 20 to about 80 weight per cent, based on totalpolyoxyalkylene content. Usually, the weight per cent of oxyethylene isabout the same as the weight per cent of oxypropylene.

Also included within the scope of the present invention is the use ofthe beta-amino carbonyl catalysts in combination with organicsurfactants. When used, the organic surfactant is usually a non ionicsurfactant such as: the polyoxyalkylene ethers of high alcohols havingfrom 10 to 18 carbon atoms including mixtures thereof; andpolyoxyalkylene ethers of alkyl-substituted phenols in which the alkylgroup can have from 6 to 15 carbon atoms. The length of the ether chainis such that appropriate hydrophilic character is provided to balancethe hydrophobic portion derived from the alcohol or phenol and renderthe compound miscible with water. The chain may contain oxyethyleneunits either as essentially the sole type of unit or oxyethylene incombination with a minor amount of oxypropylene. It is preferred thatthe hydrophilic portion of the non ionic surfactants be composedessentially of oxyethylene monomeric units. Usually the average numberof such --OC₂ H₄ -- units ranges from about 4 to about 20, althoughupwards of 30 such units can also be present.

Typical examples of non ionic surfactants which can be used incombination with the beta-amino carbonyl catalysts employed in thepractice of this invention are the adducts produced by reaction of fromabout 4 to about 30 moles of ethylene oxide per mole of any of thefollowing hydrophobes including mixtures thereof: n-undecyl alcohol,myristyl alcohol, lauryl alcohol, trimethyl nonanol, tridecyl alcohol,pentadecyl alcohol, cetyl alcohol, oleyl alcohol, stearyl alcohol,nonylphenol, dodecylphenol, tetradecylphenol, and the like. Especiallysuitable for use as the carrier medium for the beta-amino carbonylcatalysts described herein are the ethylene oxide adducts of nonylphenolhaving the average composition, C₉ H₁₉ --C₆ H₄ ---(OC₂ H₄)_(h) --OH,wherein h has an average value from about 4 to about 20, inclusive ofwhole and fractional numbers, such as 6, 9, 10.5 and 15.

The above-described solution compositions may contain from about 10 toabout 90 weight per cent of total beta-amino carbonyl catalysts(inclusive of supplementary tertiary amine catalyst, when used), basedon the combined weight of catalyst, solvent and/or organic surfactant,depending upon whether the catalyst is employed in combination witheither one or both of the solvent and organic surfactant.

It is often desirable to include as a further component of the foamformulation a minor amount of certain metal catalysts, particularlyorganic derivatives of tin including stannous and stannic compounds.Such metal co-catalysts are well known to the art and are usuallyemployed in producing polyether polyol-based polyurethanes. Illustrativeof suitable organic tin compounds are the following which may beemployed individually or in combination: stannous salts of carboxylicacids such as stannous octoate, stannous oleate, stannous acetate andstannous laurate; dialkyltin dicarboxylates such as dibutyltindilaurate, dibutyltin diacetate, dilauryltin diacetate, dibutyltindi(2-ethylhexanoate) and other such tin salts as well as dialkyltinoxides, trialkyltin oxides, tin mercaptides such as, for example,di-n-octyl tin mercaptide, and the like. When used, the amount of suchmetal co-catalysts ranges from about 0.001 to about 2 parts by weightper 100 parts by weight of total polyol reactant. In flexible foamformulations, the metal co-catalyst is preferably used in an amount fromabout 0.01 to about 0.6 p.p.h.p., and most preferably in an amount nomore than about 0.5 p.p.h.p.

Foaming is accomplished by the presence in the reaction mixture ofvarying amounts of a polyurethane blowing agent such as water which,upon reaction with isocyanate, generates carbon dioxide in situ, orthrough the use of blowing agents which are vaporized by the exotherm ofthe reaction, or by a combination of the two methods. These variousmethods are known in the art. Thus, in addition to or in place of water,other blowing agents which can be employed in the process of thisinvention include methylene chloride, liquefied gases which have boilingpoints below 80° F. and above -60° F., or other inert gases such asnitrogen, carbon dioxide added as such, methane, helium and argon.Suitable liquefied gases include aliphatic and cycloaliphaticfluorocarbons which vaporize at or below the temperature of the foamingmass. Such gases are at least partially fluorinated and may also beotherwise halogenated. Fluorocarbon agents suitable for use in foamingformulations of this invention include: trichloromonofluoromethane:dichlorodifluoromethane: 1,1-dichloro-1-fluoroethane;1,2,2-trifluoro-1,1,2-trichloroethane;1,1,1-trifluoro-2-fluoro-3,3-difluoro-4,4,4trifluorobutane;hexafluorocyclobutene; and octafluorocyclobutane. Another useful classof blowing agents include thermally-unstable compounds which liberategases upon heating, such asN,N'-dimehtyl-N,N'-dinitrosotere-phthalamide, and the like.

Generally, the blowing agent is employed in an amount from about 1 toabout 45 parts by weight per 100 parts by weight of total polyolreactant, the particular blowing agent and amount thereof depending uponthe type of foam product desired. Flexible foam formulations includingthose which favor formation of high-resilience foam, are most usuallywater blown, although a minor proportion such as up to about 10 weightper cent of total blowing agent may be constituted of a fluorocarbonsuch as trichlorofluoromethane. Flexible foam formulations usuallycontain no more than about 10 p.p.h.p. of water. For rigid formulations,blowing action is usually supplied employing a fluorocarbon in arelatively high proportion such as from about 10 to about 45 p.p.h.p.,either as the sole type of agent or in combination with a minor amountof water such as up to about 10 weight per cent of total blowing agent.The selection and amount of blowing agent in any particular foamformulation is well within the skill of the cellular polyurethane art.

In producing cellular polyurethanes in accordance with the method ofthis invention, a minor amount of an organosilicone surfactant may alsobe present as an additional component of the polyurethane-formingreaction mixture. When used, such surfactants are usually present inamounts up to about 5 parts by weight per 100 parts by weight of totalpolyol reactant.

Among the suitable classes of surfactant are thepolysiloxane-polyoxyalkylene block copolymers wherein the respectiveblocks are joined through silicon-to-carbon orsilicon-to-oxygen-to-carbon bonds and the respective polyoxyalkyleneblocks are bonded to different silicon atoms of the polysiloxanebackbone to form a comb-like structure. Usually, the polysiloxane blocksare trialkysiloxy-endblocked. In addition to the siloxy units to whichthe pendant polyoxyalkylene chains are bonded, the polysiloxane backboneis formed of difunctional siloxy units wherein the respective tworemaining valences of silicon are satisfied by bonds to organicradicals. Illustrative of such organic radicals are the hydrocarbylgroups having from 1 to 12 carbon atoms including alkyl, aryl, aralkyl,bicycloheptyl and halogen-substituted derivatives of such groups. Thepolyoxyalkylene blocks are usually constituted of oxyethylene units,oxypropylene units or a combination of such units, and thepolyoxyalkylene chains are hydroxyl-terminated or capped with amonovalent organic group such as alkyl, aryl, aralkyl, acyl, carbamyland the like. Especially useful as stabilizers of flexiblepolyether-based polyurethane foams are the block copolymers described inU.S. Pat. No. 3,505,377, an application for reissue of which was filedon Nov. 18, 1971 as Ser. No. 200,242 of Edward L. Morehouse, now U.S.Reissue Pat. No. 27,541. The copolymers of the latter patent containfrom 40 to 200 dimethylsiloxy units as essentially the sole type ofdifunctional unit, and from 15 to 60 weight per cent of the oxyalkylenecontent of the polyoxyalkylene blocks is constituted of oxyethylene.Also useful as stabilizers of flexible, polyether-based polyurethanefoam including flame-retarded foam, are the block copolymers describedin U.S. Pat. 3,657,305. The polysiloxane backbone of the organosiliconesof the latter patent, contains an average of from 10 to 200dimethylsiloxy units in combination with from 1 to 50methyl-aralkylsiloxy units such as, in particular,methyl-phenylethylsiloxy units [(CH₃)(C₆ H₅ CH₂ CH₂)SiO]. Other usefulfoam stabilizers for flexible polyether-based foam are the blockcopolymers described in U.S. Pat. No. 3,686,254. Particularly usefulstabilizers of flexible polyester-based polyurethane foam are thesurfactants described in U.S. Pat. No. 3,594,334.

A second type of foam-stabilizing component which can be present in theformulations described herein are the branched block copolymersdescribed in U.S. Pat. No. 2,834,748. Organosilicone foam stabilizersdescribed in the latter patent include those containing a trifunctionalsiloxy unit to which three polyoxyalkylene blocks are bonded throughdialkylsubstituted siloxy units. A preferred group are those having theformula MeSi[(OSiMe₂)_(x) (OC_(a) H_(2a))_(v) OX]₃, wherein Me ismethyl, x has a value of at least one, a is from 2 to 3, v has a valueof at least 5, and X is hydrogen or a monovalent hydrocarbyl group suchas lower alkyl, butyl being especially suitable.

Particularly useful as foam-stabilizing components of flame-retardedflexible polyurethane formulations are the block copolymers wherein thepolysiloxane blocks are trialkylsiloxy-endblocked and containreoccurring difunctional dialkylsiloxy monomeric units in combinationwith reoccurring difunctional cyanoalkyl-alkylsiloxy orcyanoalkoxy-alkylsiloxy monomeric units, the mole ratio of thedialkylsiloxy units to the cyano-substituted siloxy units being about10-200:3-100, and wherein the polysiloxane and polyoxyalkylene blocksare joined through an Si-C or an Si-O-C linkage, and from about 20 toabout 65 weight per cent of the oxyalkylene content of thepolyoxyalkylene blocks is constituted of oxyethylene units. These blockco-polymers are described and claimed in copending application Ser. No.279,883, filed Aug. 11, 1972, in the names of Bela Prokai and BernardKanner, now U.S. Pat. No. 3,741,917. A preferred class of suchsurfactants are the cyanopropyl-substituted block copolymers having theaverage formula, ##STR13## wherein: Me represents methyl; W represents amonovalent hydrocarbyl group (R'-), an acyl group [R'C(O)-] or acarbamyl group [R'NHC(O)-], wherein R' has from 1 to 12 carbon atoms; xhas an average value of from about 20 to about 100; y has an averagevalue of from about 4 to about 30; z has an average value of from about2 to about 10; a has a value of from 2 to 4, provided from about 20 toabout 65 weight per cent of the oxyalkylene units of the polyoxyalkylenechain, --(C_(a) H_(2a) O)_(b) --, are constituted of oxyethylene; and bhas an average value such that the average molecular weight of thepolyoxyalkylene chain is from about 1000 to about 6000.

Because of the high reactivity of high-resilience foam formulations, thefoams are generally self-stabilizing and can be obtained without the useof stabilizing agents. However, it is usually desirable to include asilicone surfactant as an additional component of such formulations inorder to minimize the tendency of the foam to settle and to control celluniformity. Particularly effective for this purpose are the relativelylow molecular weight polyoxyalkylene-polysiloxane block copolymersdescribed and claimed in copending application Ser. No. 84,181, filedOct. 26, 1970, of Edward L. Morehouse, now U.S. Pat. No. 3,741,917.Especially suitable as components of high-resilience formulations arethe block copolymers described therein having the formula, ##STR14##wherein: x has an average value of from 2 to 7; y has a value from 3 to10; z has an average value from 2 to 6; a and d each has a value from 2to 4; and R" is a monovalent hydrocarbon radical such as alkyl, aralkyland aryl radicals, or an acyl group.

Also suitable as organosilicone components of high-resilience foamformulations are the relatively low molecular weight aralkyl-modifiedpolymethylsiloxane oils described and claimed in copending applicationSer. No. 305,713, filed Nov. 13, 1972, in the name of Edward L.Morehouse, and entitled, "Polyether Urethane Foam," now U.S. Pat. No.3,839,384.

When used, the organosilicone component is usually present inhigh-resilience formulations in an amount between about 0.025 and about2 parts by weight per 100 parts by weight of total polyol reactant.

Illustrative of suitable surfactant components of rigid foamformulations are copolymers wherein the polyoxyalkylene blocks arehydroxyl-terminated such as those described in U.S. Pat. No. 3,600,418.

The beta-amino carbonyl catalysts described herein are also effectivecatalytic components of flame-retarded foam formulations. Theflame-retardants can be chemically combined in one or more of the othermaterials used (e.g., in the polyol or polyisocyanate), or they can beused as discrete chemical compounds added as such to the foamformulation. The organic flame-retardants preferably contain phosphorusor halogen, or both phosphorus and halogen. Usually, the halogen, whenpresent, is chlorine and/or bromine. Flame-retardants of the discretechemical variety include: 2,2-bis(bromomethyl)-1,3-propane-diol (alsoknown as dibromoneopentyl glycol); 2,3-dibromopropanol;tetrabromophthalic anhydride; brominated phthalate ester diols such asthose produced from tetrabromophthalic anhydride, propylene oxide andpropylene glycol; tetrabromobisphenol-A; 2,4,6-tribromophenol;pentabromophenol; brominated anilines and dianilines;bis(2,3-dibromopropyl)ether of sorbitol; tetrachlorophthalic anhydride,chlorendic acid; chlorendic anhydride; diallyl chlorendate; chlorinatedmaleic anhydride; tris(2-chloroethyl)phosphate [(ClCH₂ CH₂ O)₃ P(O)];tris(2,3-dibromopropyl)phosphate; tris(1,3-dichloropropyl)phosphate;tris(1-bromo-3-chloroisopropyl)phosphate;tris(1,3-dichloroisopropyl)phosphate; bis(2,3-dibromopropyl) phosphoricacid or salts thereof; oxypropylated phosphoric and polyphosphoricacids; polyol phosphites such as tris(dipropylene glycol)phosphite;polyol phosphonates such as bis(dipropylene glycol)hydroxymethylphosphonate; di-poly(oxyethylene)hydroxymethyl phosphonate;di-poly(oxypropylene)phenyl phosphonate;dipoly(oxypropylene)chloromethyl phosphonate; di-poly(oxypropylene)butylphosphonate and 0,0-diethyl-N,N-bis(2-hydroxyethyl)aminomethylphosphonate. Also suitable are compounds having the formulas: ##STR15##Other suitable flame-retardants comprise halogen-containing polymericresins such as polyvinylchloride resins in combination with antimonytrioxide and/or other inorganic metal oxides such as zinc oxide, asdescribed in U.S. Pat. Nos. 3,075,927; 3,075,928; 3,222,305; and3,574,149. It is to be understood that other flame-retardants known tothe art may be used and that the aforesaid compounds may be employedindividually or in combination with one another.

When used, the flame-retarding agent can be present in the foamformulations described herein in an amount from about 1 to about 30parts by weight per 100 parts by weight of the polyol reactant, theparticular amount employed depending largely on the efficiency of anygiven agent in reducing flammability.

If desired, other additional ingredients can be employed in minoramounts in producing the polyurethane foams in accordance with theprocess of this invention. Illustrative of such additives that can beemployed are: the aforementioned cross-linking agents such as glycerol,diethanolamine, triethanolamine and their oxylakylene adducts; additivesto enhance load-bearing properties such asmethylene-di-ortho-chloroaniline (MOCA); as well as fillers, dyes,pigments, anti-yellowing agents and the like.

The cellular urethane polymers of the invention may be formed inaccordance with any of the processing techniques known to thepolyurethane art such as the "one-shot" , quasi-prepolymer andprepolymer techniques. For example, in accordance with the "one-shot"process, foamed products are produced by carrying out the reaction ofthe polyisocyanate and the polyol reactants in the presence of thebeta-amino carbonyl-containing catalyst systems described herein,simultaneously with the foaming operation. This one-step process isusually employed in producing flexible foam including high-resiliencefoam, although it is also applicable to rigids. In preparing foamedproducts in accordance with the quasi-prepolymer technique, thepolyisocyanate is first reacted with a portion of the polyol reactant togive a product having a high percentage of free --NCO groups (e.g., from20 to 50 per cent), and the product is subsequently foamed by reactionwith additional polyol and foaming agent in the presence of thebeta-amino carbonyl catalysts. In the prepolymer technique, thepolyisocyanate is reacted with a slightly less than stoichiometricquantity of the polyol reactant to form a prepolymer having a lowpercentage (e.g., from 1 to 10 per cent) of free --NCO groups, followedby reaction of the prepolymer with a blowing agent such as water in thepresence of the catalyst systems described herein to form the cellularmaterial. These various multi-stage methods are more usually applied torigid formulations.

In general, final or post-curing of the foam products is achieved byallowing the foam to stand at ambient temperatures until a tack-freeproduct is obtained, or by subjecting the foam to elevated temperaturesup to about 500° F. in order to achieve more rapid curing. In view ofthe higher reactivity of the combination of reactants employed inproducing high-resilience foams, however, a sufficiently high degree ofcuring is achieved during form formulation without the necessity ofsubjecting the foam to conventional high temperature (e.g., 300°-500°F.) post-curing procedures which are otherwise applied in the commercialmanufacture of flexible foams from less highly reactive flexible foamformulations.

In the specific application of the beta-amino amides and beta-aminoesters described herein as catalytic components of molded,high-resilience foam formulations, the mold is charged with the foamablereaction mixture either at ambient temperature or pre-heated to atemperature of from about 70° F. to about 200° F., in an amountsufficient to at least completely fill the mold. The mold is then closedand the reaction mixture is allowed to foam and cure itself. In view ofthe excellent mold-release characteristics of the high-resilience foamsproduced in accordance with the present invention, the foamed product isreadily removed from the mold without substantial damage to the foamsurface. The demolded foam is suitable for end-use application withoutfurther curing. It is to be understood, however, that such foam may besubjected to further curing, as desired.

The end-use applications of cellular polyurethanes are well known. Thus,the polyurethane foams produced in accordance with the present inventionare useful as textile interliners, cushioning material, mattresses,paddings, carpet underlay, packaging, gaskets, sealers, thermalinsulators and the like.

The following examples are offered as further illustrative of thepresent invention and are not to be construed as unduly limiting.

Examples 1-10 describe the preparation of illustrative beta-aminocarbonyl catalysts, designated herein as Amine Catalysts I-X,respectively, which were employed as catalyst components in thepolyurethane foam preparations of the remaining examples. Of these,Amine Catalysts IV, V, VI and VII are novel compounds. In Examples 1-10,the amine reactant was substantially anhydrous and the reaction mediacontained less than about 5 weight per cent water, expressed on thebasis of amine reactant. The yields of product are based on the numberof moles of reactant present in the limiting amount.

EXAMPLES 1-4

In accordance with these examples beta-dialkylamino-N,N-dialkylamides,designated herein as Amine Catalysts I-IV, respectively, were preparedby the reaction of secondary amines (Reactant A) and alkyl esters ofalpha,beta-unsaturated carboxylic acids (Reactant B) in the presence ofphenothiazine (0.7 gram) and p-methoxyphenol (0.7 gram) as inhibitors,under elevated temperature and pressure conditions in a stainless steelrocker bomb. The particular reactants, relative proportions thereof andreaction conditions of temperature, pressure and time are given in TableI. After the indicated reaction time, the reactors were cooled and therespective reaction mixtures were transferred to a still except that, inExample 1, the reaction mixture was partially stripped of volatilesafter discharge from the pressure reactor and a portion (200 grams) ofthe partially stripped material was combined with phenothiazine (1.0gram), p-methoxyphenol (0.5 gram) and Humble 1243 oil as a pot-boiler(20 grams). In each example, the respective products were recovered bydistillation under the temperature and reduced pressure conditionsspecified in Table I. Of these products, Amine Catalysts I, II and IIIare known compounds and were produced in a purity of about 75-98 percent, as indicated by gas chromatographic analysis. Amine Catalyst IV isa novel compound and its structure was verified by infrared and nuclearmagnetic resonance spectroscopy.

                                      TABLE I                                     __________________________________________________________________________                           Reactant                                                                            Reactant                                                                             Temper-                                                                            Pres-     Product Recovery           Ex.                                                                              Beta-Amino Amide Catalyst                                                                         A     B      ature                                                                              sure  Time    mm. Yield              No.                                                                              No.                                                                              Structure        (grams)                                                                             (grams)                                                                              (°C.)                                                                       (p.s.i.g.)                                                                          (hours)                                                                           °C.                                                                        Hg  %                  __________________________________________________________________________    1  I  3-dimethylamino-N,N-                                                                           Dimethyl-                                                                           Ethyl  180-200                                                                            200-400                                                                             20  103-105                                                                           10  95                       dimethylpropionamide                                                                           amine acrylate                                                                (419) (300)                                                  (CH.sub.3).sub.2 NCH.sub.2 CH.sub.2 C(O)N(CH.sub.3).sub.2               2  II 3-dimethylamino-2-methyl-                                                                      Dimethyl-                                                                           Methyl 190-200                                                                            400-500                                                                             20  61-62                                                                             3   44                       N,N-dimethylpropionamide                                                                       amine methacrylate                                                            (135) (100)                                                   ##STR16##                                                              3  III                                                                              3-diethylamino-N,N-                                                                            Diethyl-                                                                            Methyl 180-200                                                                            200-320                                                                             32  90-91                                                                             3   22                       diethylpropionamide                                                                            amine acrylate                                               (C.sub.2 H.sub.5).sub.2 NCH.sub.2 CH.sub.2 C(O)N(C.sub.2 H.sub.5).su          b.2              (219) (86.1)                                                 (C.sub.2 H.sub.5).sub.2 CH.sub.2 CH.sub.2 C(O)N(C.sub.2 H.sub.5).sub          .2                                                                      4  IV 3-dimethylamino-N,N-                                                                           Dimethyl-                                                                           Methyl 185-205                                                                            250-350                                                                             32  74-79                                                                             2   34                       dimethylbutyramide                                                                             amine crotonate                                               ##STR17##       (117) (81)                                             __________________________________________________________________________

EXAMPLE 5 Preparation of 3-Diethylamino-N,N,-Dimethylpropionamide

In accordance with this example, anhydrous diethylamine (44 grams) andN,N-dimethylacrylamide (60 grams) were heated at reflux temperature(about 56°-60° C.) for 48 hours. After this period of time, the reactionmixture was subjected to distillation to separate unreacted amine andamide followed by recovery of product in 86 per cent yield at 70° C. and2 mm. mercury pressure. The liquid product (purity = about 95 per cent)is designated herein as Amine Catalyst V, and has the formula, (C₂ H₅)₂N-CH₂ CH₂ C(0)N(CH₃)₂. The structure of this novel product was confirmedby infrared functional analysis and purity by gas-liquid chromatographicanalysis.

EXAMPLE 6 Preparation of 3-(N-Morpholino)-N',N'-Dimethylpropionamide

Morpholine (45 grams) was added dropwise to a stirred reaction flaskcontaining N,N-dimethylacrylamide (50 grams). After the addition wascompleted, the reaction mixture was stirred for 24 hours at 30°-70° C.After this period of time, the reaction mixture was heated at 110° C.and 10 mm. mercury pressure to remove unreacted starting materials. Theremaining material was a viscous liquid and was recovered in a 95 percent yield. This residue product contains about 98 weight per cent ofthe novel compound, ##STR18## and is designated herein as Amine CatalystVI. A sample of this material was distilled at 114°-115° C. and 1 mm.mercury pressure without appreciable decomposition. The structure wasverified by infrared and nuclear magnetic resonance spectroscopy.

EXAMPLE 7 Preparation ofN,N'-Piperazino-bis[3-(N",N"-dimethylpropionamide)]

To a stirred solution of piperazine (25.0 grams) dissolved in ethanol(30 grams), N,N-dimethylacrylamide (59.4 grams) was added. After theaddition, the reaction mixture was stirred at 30°-40° C. for 2 hours.The precipitated material was filtered, washed with ethanol and driedunder vacuum. The solid product (76 per cent yield) has a melting pointof 137°-138° C. and the structure: ##STR19## as determined by infraredand nuclear magnetic resonance spectroscopy and elemental analysis.Anal. Calcd. for C₁₄ H₂₈ N₄ O₂ : C, 59.1; H, 9.9; N, 19.7. Found: C,58.0 and 58.4; H, 9.59 and 9.52; N, 19.5 and 19.4. This novel product isdesignated herein as Amine Catalyst VII.

EXAMPLE 8 Preparation of Ethyl 3-(N,N-Dimethylamino)propionate

To a chilled (-15° C.) reaction vessel there was added; anhydrousdimethylamine (100 grams); ethyl acrylate (250 grams); phenothiazine(0.5 gram); and p-methoxyphenol (0.5 gram). The mixture was maintainedat -13° C. for 2 hours with stirring after which the temperature wasallowed to rise to about 25° C. Unreacted dimethylamine and ethylacrylate were removed by distillation. The product was recovered bydistillation at 58° C. and 10 mm. mercury pressure in a yield of 97 percent. The product, designated herein as Amine Catalyst VIII, has theformula, (CH₃)₂ NCH₂ CH₂ C(O)OC₂ H₅, as verified analytically byinfrared spectroscopy.

EXAMPLE 9 Preparation of Ethyl 3-(N,N-Diethylamino)propionate

The following materials were charged to the reaction vessel: anhydrousdiethylamine (292 grams); ethyl acrylate (200 grams); phenothiazine (1.0gram); and p-methoxyphenol (1.0 gram). This mixture was heated at reflux(about 56°-60° C.) for 24 hours. At the end of this period, unreactedamine was removed by distillation. The product was recovered at 80°-81°C. and 10 mm. mercury pressure in a yield of 96 percent. The product isdesignated herein as Amine Catalyst IX and has the formula, (C₂ H₅)₂N-Ch₂ CH₂ -C(O)OC₂ H₅, as verified analytically by infraredspectroscopy.

EXAMPLE 10 Preparation of 2-(N,N-dimethylamino)ehtyl3-(N',N'-dimethylamino)propionate

Anhydrous dimethylamine (19.8 grams) was added dropwise to2-(N,N-dimethylamino)ethyl acrylate (31.5 grams) in amagnetically-stirred, ice-cooled reaction vessel at such a rate that thetemperature did not exceed 40° C. The addition of dimethylamine wascomplete in about 10 minutes. After allowing the reaction mixture tostir overnight at room temperature, it was subjected to reduced pressure(about 20 mm. Hg) to remove unreacted dimethylamine. Gas-liquidchromatographic analysis indicated that the residue product was 96.5 percent pure. The structure of the product, ##STR20## was verifiedspectroscopically (nuclear magnetic resonance and infrared) and byelemental analysis. Anal. Calc'd. for C₉ H₂₀ N₂ O₂ : C, 57.4; H, 10.6;N, 14.9. Found: C, 57.3; H, 10.5; N, 14.8. This product is designatedherein as Amine Catalyst X.

In the examples which follow, molded and freerise cellular polyurethaneswere prepared employing the above-described Amine Catalysts I-X ascatalytic components of a variety of foam formulations. In someexamples, these beta-amino amide and ester catalysts were used as thesole tertiary amine catalytic component of the reaction mixtures whereasin other instances they were used as components of mixed catalystsystems. In preparing the molded foams of Examples 11-16, the procedureemployed was that described below as Foam Procedure I. The manipulativesteps involved in the preparation of the free-rise foams of Examples17-46 were as described under Foam Procedure II.

FOAM PROCEDURE I

An aluminum mold (4" or 21/2" = 15" × 15") is prepared by first waxinglightly with Brulin Permamold release Agent and then pre-heating in a140° C. oven for about 10 minutes to raise the temperature of the moldto 175°-200° F. Excess mold-release agent is wiped off and the mold isallowed to cool to 120° F. before foaming. The initial mixing of thecomponents of the foam formulation is started when the mold is cooled toabout 130° F. The purpose of pre-heating the mold to the initial hightemperature is to remove solvent from the mold-release agent. Allcomponents of the reaction mixture, except the polyisocyanate reactant,are measured or weighed into a one-half gallon, five inch diameter,cylindrical, cardboard carton and mixed 60 seconds with a 21/2 inch.6-blade turbine at 4000 revolutions per minute. The polyisocyanatereactant is then weighed into the mixture of other components,stainless-steel baffles designed for the 1/2-gallon carton are inserted,and mixing is continued for 5 seconds. The carton is then lowered toallow the mixer to drain, and the contents are quickly poured into themold. The mold lid is closed and clamps are placed around the mold topermit flashout. "Exit time" is observed and defined as the time whenall four top holes of the mold are full, that is, when the foam beginsto exude from all four holes of the mold. "Pop time" is observed anddefined as the time when extruded parts stop bubbling. The 4" mold isdemolded after standing at room temperature for 10 minutes whereas the21/2" mold is demolded after 8 minutes. After trimming around the edgeswith scissors, the foam sample is weighed before running through rollersfour times to crush cells open, and is then allowed to cure for threedays at room temperature before being submitted for physical propertymeasurements.

FOAM PROCEDURE II

The polyol and polyisocyanate reactants and surfactant (and, whenemployed, the flame-retardant and cross-linking agents) are weighed intoa 1/2-gallon, five-inch diameter, cylindrical cardboard carton. Thewater and catalytic amine components are measured and blended togetherin a small beaker. The tin catalyst is measured into a hypodermicsyringe. Eleven stainless-steel baffles are inserted into the carton andcentered on a drill press equipped with a 1.65-inch, 4-blade turbine. Atimer is pre-set for a total of 90 seconds. The mixer is started at 2400revolutions per minute and continued for 60 seconds, except that inthose formulations containing polymer/polyols, the mixer is started at3000 revolutions per minute. The mixer is stopped manually for a15-second de-gassing period. At 75 seconds on the timer, mixing iscontinued for 5 seconds before adding the aqueous amine premix. Mixingis continued 5 seconds and the tin catalyst is added after an additional5 seconds of mixing. The blended contents are poured into a 14" × 14" ×6" cardboard box. Both the "cream time" and "rise time" are recordedwhich terms denote the interval of time from the formation of thecomplete foam formulation to: (1) the appearance of a creamy color inthe formulation, and (2) the attainment of the maximum height of thefoam, respectively. The foam is allowed to stand at room temperature forabout one day before being submitted for physical property measurements.

The physical properties which were determined for the flexible foamsproduced in the examples and control runs were measured in accordancewith the standardized test procedures given below.

Porosity (Air), which is a comparative measurement of the degree ofopenness of the cells of flexible foams, was determined in accordancewith the following test procedure: The test specimen of foam (4" × 4"×1/2") is compressed between two pieces of flanged plastic tubing (21/4"I.D.) of an air porosity assembly maintained under an air pressure of14.7 pounds. Air is drawn through the thickness (1/2") of the foamspecimen at a velocity controlled to maintain a differential pressure of0.1 inch of water across the thickness dimension. The air flow necessaryto develop the requisite pressure differential is recorded and the airflow per unit area of the foam specimen is reported as the porosity ofthe foam.

Resiliency of both the molded and free-rise foams was determined inaccordance with ASTM D-1564-69.

Density, Tensile Strength, Elongation, Tear Resistance and CompressionSet were measured as described under (1) ASTM D-2406-68 for the moldedfoams produced in accordance with Foam Procedure I, and (2) ASTMD-1564-69 for the free-rise foams produced in accordance with FoamProcedure II.

Indentation Load Deflection (ILD Values) to 25% and 65% deflections weremeasured in accordance with (1) ASTM D-2406-68 for the molded foamsamples, the thickness of the sample being 21/2" or 4" depending uponwhether the 21/2" or 4" mold was used, and (2) ASTM D-1564-69 for thefree-rise foams, the test sample being cut to a 4" thickness. ReturnValue is the percentage ratio of the load required to support the return25% indentation after one minute as compared to the load required tosupport the initial 25% indentation after one minute. Load Ratio is theratio of the 65% and 25% ILD values, respectively.

The following Examples 11-16 demonstrate the efficacy and advantages ofbeta-amino amide and ester catalysts described herein when employed asdirect replacements for N-ethylmorpholine in high-resilience foamformulations.

EXAMPLES 11 and 12

Molded foams were prepared employing 3-dimethylamino-N,N-dimethylpropionamide (Amine Catalyst I) in Example 11,2-(N,N-dimethylamino)ethyl 3-dimethylaminopropionate (Amine Catalyst X)in Example 12, and N-ethylmorpholine in Control Run K-1, as catalyticcomponents of a high-resilience foam formulation, designated herein asFoam Formulation A. The composition of this reaction mixture as employedin Examples 11 and 12 and Control Run K-1 is given in Table II whichfollows.

                                      TABLE II                                    __________________________________________________________________________    FOAM FORMULATION A                                                            __________________________________________________________________________                               Parts By Weight                                                               Control                                                                            Examples                                              Component          K-1  11 and 12                                     __________________________________________________________________________    Polyol A: An ethylene oxide-capped, glycerol-                                                            60   60                                            started poly(oxypropylene) triol having a                                     Hydroxyl No. of about 34, a molecular weight                                  of about 5000, and a primary hydroxyl content                                 of 70-75 mole per cent.                                                       Polyol B: A polymer/polyether polyol having                                                              40   40                                            a Hydroxyl No. of about 28 and based on (parts                                by weight): styrene (10), acrylonitrile (10) and                              Polyol A (80), produced by polymerizing said                                  monomers in Polyol A.                                                         Polyisocyanate A: A mixture of: (1) 80 weight per                                                        36.45                                                                              36.45                                         cent of the 2,4- and 2,6- isomers of tolylene                                 diisocyanate, the weight ratio of said isomers                                being 80:20, respectively; and (2) 20 weight per                              cent of a polyphenylmethylene polyisocyanate                                  having an average -NCO functionality of 2.7 and                               a free -NCO content of 30.5-32.3 weight per cent.                             Water                      3.0  3.0                                           Amine Catalysts                                                               Amine Catalyst A: A 70 weight per cent solution                                                          0.08 0.08                                          of bis[2-(N,N-dimethylamino)ethyl]ether in                                    dipropylene glycol.                                                           Amine Catalyst B: A 33 weight per cent solution                                                          0.25 0.25                                          of triethylenediamine in dipropylene glycol.                                  N-Ethylmorpholine          0.80 None                                          Amine Catalysts I and X, respectively.                                                                   None 0.20                                          Dibutyltin dilaurate       0.03 0.03                                          Surfactant A /1/           0.07 --                                            Surfactant B /2/           --   0.05                                          __________________________________________________________________________     /1/ A phenylethyl-modified polymethylsiloxane oil having the average          composition, Me.sub.3 SiO(Me.sub.2 SiO).sub.x [(C.sub.6 H.sub.5 C.sub.2       H.sub.4)(Me)SiO] .sub.y SiMe.sub.3 wherein Me represents methyl and the       average values of x and y are 3.0 and 1.5, respectively.                      /2/ Same as Surfactant A, except average values of x and y are 3.8 and        1.9, respectively.                                                       

The foams of Examples 11 and 12, designated for convenience as Foam Nos.1 and 2, respectively, as well as Control Foam K-1, were preparedfollowing Foam Procedure I, employing the 4" × 15" × 15" aluminum moldheated to 120° F. Upon completion of foam formation, Control Foam K-1was easily removed from the mold after 10 minutes residence time andfoam surface and freedom from tendency to shrink were excellent.However, the odor level emanating from the freshly demolded foam wasvery high and, although diminishing in intensity with time, this odorpersisted for several hours. With respect to Foam No. 1, demoldcharacteristics were also excellent and the cellular structure was fine(as opposed to coarse). In the case of Foam No. 2, demoldcharacteristics were good and, although the foam surface structure wasnot as good as that of Control Foam K-1 or Foam No. 1, it wassatisfactory. With respect to both Foam Nos. 1 and 2, the odor levelemanating from the freshly demolded foam was very low and clearly animprovement over the control foam. These and other results as well asphysical property data of the respective foams are given in Table III.

                  TABLE III                                                       ______________________________________                                        HIGH-RESILIENCE FOAM (Molded)                                                 ______________________________________                                        Example No.          --      11      12                                       Control Run          K-1     --      --                                       Foam No.             K-1     1       2                                        Foam Formulation A                                                            N-Ethylmorpholine, p.p.h.p.                                                                        0.80    None    None                                     Amine Catalyst I /1/, p.p.h.p.                                                                     None    0.20    --                                       Amine Catalyst X /2/, p.p.h.p.                                                                     None    --      0.20                                     Exit Time, seconds   61      53      59                                       Pop Time, seconds    121     100     110                                      Hot Foam Odor        High    Low     Low                                      Foam Properties                                                               Basal cell structure Good    Good    Fair                                     Resilience, % ball rebound                                                                         63      64      64                                       Porosity, ft..sup.3 /min./ft..sup.2                                                                61      53.1    50.6                                     Density, lbs./ft..sup.3                                                                            1.96    1.90    1.93                                     ILD (4"), lbs./50 in..sup.2                                                    25% deflection      22.3    20.3    24.2                                      65% deflection      62.0    56.0    63.0                                      25% return          17.3    16.0    19.0                                      Return value, %     77.6    78.8    78.5                                     Load Ratio           2.78    2.76    2.62                                     Compression Sets, %                                                            75%                 13.0    12.6    13.0                                      50% After Humid Aging /3/                                                                         26.5    24.9    24.2                                     Tensile strength, p.s.i.                                                                           24.0    22.6    21.8                                     Elongation, %        199     204     192                                      Tear Resistance, lbs./in.                                                                          2.41    2.22    2.17                                     Humid Age Load Loss, % /3/                                                                         22.4    20.6    20.2                                     ______________________________________                                         /1/ 3-Dimethylamino-N,N-dimethylpropionamide.                                 /2/ 2-(N,N-Dimethylamino)ethyl 3-Dimethylaminopropionate.                     /3/ Five hours at 120° C. in 100% relative humidity.              

The results of Table III show that the improvement of low residual foamodor afforded by the catalysts of this invention is achieved withoutsacrifice of the good overall combination of physical propertiespossessed by the control foam. Further, as evinced by the interval oftime required for the foam to exude from the mold, the reactivity of therespective reaction mixtures containing Amine Catalysts I and X wasexcellent even though the concentration of these catalysts was onlyone-fourth the concentration (on a weight basis) of N-ethylmorpholine.In fact, as reflected by comparison of the respective exit times, thereactivity of the formulation containing3-dimethylamino-N,N-dimethylpropionamide (Example 11) in an amount of0.20 part per 100 parts of total polyol (p.p.h.p.), was 12-14 per centhigher than that of the control formulation containing 0.80 p.p.h.p. ofN-ethylmorpholine.

EXAMPLES 13-16

In accordance with these examples, molded foams were prepared employingAmine Catalysts II-V, respectively, as direct replacements forN-ethylmorpholine (Control Run K-2) in a high-resilience foamformulation, designated herein as Foam Formulation B. The composition ofthis reaction mixture is given in the following Table IV.

                  TABLE IV                                                        ______________________________________                                        FOAM FORMULATION B                                                            ______________________________________                                                             Parts By Weight                                                                 Control  Examples                                      Component              K-2      13-16                                         ______________________________________                                        Polyol A /1/           60       60                                            Polyol B /1/           40       40                                            Polyisocyanate A /1/   34.38    34.38                                         Water                  2.80     2.80                                          Amine Catalysts                                                               Amine Catalyst A /1/   0.08     0.08                                          Amine Catalyst B /1/   0.30     0.30                                          N-Ethylmorpholine      0.80     None                                          Amine Catalysts II-V, respectively.                                                                  None     0.15                                          Dibutyltin dilaurate   0.03     0.03                                          Surfactant C /2/       1.50     1.00                                          ______________________________________                                         /1/ Same as in Foam Formulation A of Table II.                                /2/ A polysiloxane oil having the average composition, Me.sub.3               SiO(Me.sub.2 SiO).sub.4 [MeO(C.sub.2 H.sub.4 O).sub.3 C.sub.2 H.sub.4         SiMeO].sub.2.8 SiMe.sub.3 where Me is methyl, employed as a 10 weight per     cent solution in Polyol A.                                               

The foams of Examples 13-16, designated for convenience as Foam Nos.3-6, respectively, as well as Control Foam K-2 were prepared followingFoam Procedure I, employing the 21/2" × 15" × 15" aluminum mold heatedto 120° F. Upon completion of foaming, it was found that in eachinstance demold characteristics were excellent as reflected by lack offoam tenderness and ease of demolding. The surface structure of ControlFoam K-2 and Foam Nos. 3-6 was also good. However, the odor levelemanating from the freshly demolded control foam was high. With respectto Foam Nos. 3-6, on the other hand, hot foam odor was low and clearlyan improvement over that of the control foam. Other results and foamphysical property data are given in Table V.

                                      TABLE V                                     __________________________________________________________________________    HIGH-RESILIENCE FOAM (molded)                                                 __________________________________________________________________________    Example No.         --  13  14  15  16                                         Control Run No.    K-2 --  --  --  --                                        Foam No.            K-2 3   4   5   6                                         Foam Formulation B                                                            N-Ethylmorpholine, p.p.h.p.                                                                       0.80                                                                              None                                                                              None                                                                              None                                                                              None                                      Amine Catalyst II /1/, p.p.h.p.                                                                   None                                                                              0.15                                                                              --  --  --                                        Amine Catalyst III /2/, p.p.h.p.                                                                  None                                                                              --  0.15                                                                              --  --                                        Amine Catalyst IV /3/, p.p.h.p.                                                                   None                                                                              --  --  0.15                                                                              --                                        Amine Catalyst V /4/, p,.p.h.p.                                                                   None                                                                              --  --  --  0.15                                      Exit Time, seconds  45  47  48  46  49                                        Pop Time, seconds   107 114 125 112 109                                       Hot Foam Odor       High                                                                              Low Low Low Low                                       Foam Properties                                                               Basal cell structure                                                                              Good                                                                              Good                                                                              Good                                                                              Good                                                                              Good                                      Resilience, % ball rebound                                                                        60  63  61  64  63                                        Porosity, ft..sup.3 /min./ft..sup.2                                                               21.5                                                                              39.5                                                                              26.5                                                                              32.0                                                                              21.5                                      Density, lbs./ft..sup.3                                                                           2.69                                                                              2.64                                                                              2.65                                                                              2.72                                                                              2.77                                      ILD (2-1/2"), lbs./50 in..sup.2                                                25% deflection     35.5                                                                              36.0                                                                              34.9                                                                              35.4                                                                              35.0                                       65% deflection     93.2                                                                              95.7                                                                              92.3                                                                              94.9                                                                              92.6                                       25% return         28.6                                                                              29.0                                                                              28.2                                                                              28.6                                                                              28.1                                       Return value, %    80.6                                                                              80.5                                                                              80.8                                                                              80.8                                                                              80.3                                      Load Ratio          2.63                                                                              2.66                                                                              2.65                                                                              2.68                                                                              2.65                                      Compression Sets, %                                                            75%                11.1                                                                              10.4                                                                              10.4                                                                              11.1                                                                              11.4                                       50% After Humid Aging /5/                                                                        21.5                                                                              20.6                                                                              19.1                                                                              21.0                                                                              21.6                                      Tensle strength, p.s.i.                                                                           26.5                                                                              26.5                                                                              28.2                                                                              29.0                                                                              26.2                                      Elongation, %       172 177 193 186 176                                       Tear Resistance, lbs./in.                                                                         2.34                                                                              2.38                                                                              2.46                                                                              2.38                                                                              2.44                                      Humid Age Load Loss, % /5/                                                                        30.7                                                                              26.9                                                                              26.5                                                                              23.9                                                                              24.8                                      __________________________________________________________________________     /1/ 3-Dimethylamino-2-methyl-N,N-dimethylpropionamide.                        /2/ 3-Diethylamino-N,N-diethylpropionamide.                                   /3/ 3- Dimethylamino-N,N-dimethylbutyramide.                                  /4/ 3-Diethylamino-N,N-dimethylpropionamide.                                  /5/ Five hours at 120° C. in 100% relative humidity.              

The results of Table V show that the improvement in hot foam odorrealized by use of Amine Catalysts II-V in place of N-ethylmorpholinewas achieved without impairment of the overall combination of physicalproperties possessed by the control foam. Thus, the resiliency andporosity of Foam Nos. 3-6, were at least as good as that of the controlfoam and their load-bearing, compression set and other properties werealso good. In addition to the improvement in hot foam odor, the humidage load loss of Foam Nos. 3-6 was at least 12 per cent less than andthus superior to that of the control foam.

EXAMPLE 17

In accordance with this example, 3-dimethylamino-N,N-dimethylpropionamide (Amine Catalyst I) was employed in combinationwith bis[2-(N,N-dimethylamino)ethyl]ether as the amine catalysts of afree-rise, high-resilience foam formulation containingtris(2,3-dibromopropyl)phosphate as an added flame-retarding agent. Acontrol foam was also prepared (control Run K-3) employing the sameformulation except that a 33 weight per cent solution oftriethylenediamine was employed as the sole amine catalyst. Thecomposition of the respective reaction mixtures (Foam Formulation C) isgiven in Table VI. The foam of this example and the control foam wereprepared following free-rise Foam Procedure II. The results and foamphysical property data are also given in Table VI.

                  TABLE VI                                                        ______________________________________                                        HIGH-RESILIENCE FOAM (Free-Rise)                                              ______________________________________                                        Example No.               --     17                                           Control Run No.           K-3    --                                           Foam No.                  K-3    7                                            Foam Formulation C, Parts by Weight                                           Polyol B /1/              50     50                                           Polyol C: An ethylene oxide-capped, glycerol                                                            50     50                                           started poly(oxypropylene) triol having a                                     Hydroxyl No. of about 27, a molecular weight                                  of about 6000, and a primary hydroxyl content                                 of 80-85 mole per cent.                                                       Polyisocyanate B: A mixture of the 2,4- and 2,6-                                                        28.3   28.3                                         isomers of tolylene diisocyanate, the weight                                  ratio of said isomers being 80:20, respectively.                              (Index = 110)                                                                 Diethanolamine            0.8    0.8                                          Water                     2.0    2.0                                          Amine Catalysts                                                               Amine Catalyst B: A 33 weight per cent solution                                                         0.40   None                                         of triethylenediamine in dipropylene glycol.                                  Bis[2-(N,N-dimethylamino)ethyl]ether (undiluted)                                                        None   0.06                                         Amine Catalyst I /2/      None   0.24                                         Stannous octoate          0.06   0.06                                         Tris(2,3-dibromopropyl) phosphate                                                                       2.0    2.0                                          Surfactant C /3/          1.0    1.0                                          Cream Time, seconds       6      6                                            Rise Time, seconds        155    185                                          Foam Properties                                                               Resiliency, % ball rebound                                                                              62     61                                           Porosity, ft..sup.3 /min./ft..sup.2                                                                     37     40                                           Density, lbs./ft..sup.3   2.98   2.96                                         ILD (4"), lbs./50 in..sup.2                                                    25% deflection           35.2   34.3                                          65% deflection           79.3   77.2                                          25% return               28.8   27.0                                          Return value, %          81.8   78.8                                         Load Ratio                2.25   2.25                                         Compression Sets, %                                                            75%                      5.7    6.1                                           50%                      7.2    7.5                                          Tensile strength, p.s.i.  21.1   20.6                                         Elongation, %             187    177                                          Tear Resistance, lbs./in. 2.71   3.05                                         Humid Age Load Loss, % /4/                                                                              35.6   34.5                                         50% Compression Set After Humid Aging, % /4/                                                            11.9   13.4                                         ______________________________________                                         /1/ As defined in Table II.                                                   /2/ 3-Dimethylamino-N,N-dimethylpropionamide.                                 /3/ As identified in Table IV.?                                               /4/ Aged five hours at 120° C. in 100% relative humidity.         

The results of Table VI indicate that Foam No. 7 and Control Foam K-3had excellent resiliency and about the same overall combination ofphysical properties. Both foams were also of fine cell structure.Although formulation reactivity, as reflected by rise time, was higherin the case of the control reaction mixture, reactivity of the reactionmixture employed in Example 17 was good. The higher reactivity observedfor triethylenediamine is offset by a number of advantages offered byuse of 3-dimethylamino-N,N-dimethylpropionamide in combination withbis[2-(N,N-dimethylamino)-ethyl]ether. One such advantage is that thelatter catalysts are both normally liquid materials whereastriethylenediamine, although an excellent catalyst, has the processingdisadvantage of being a solid. Perhaps more significantly,triethylenediamine is also associated with a relatively strong amineodor which was noticeable as a residual odor in the freshly preparedcontrol foam. On the other hand, freshly prepared Foam No. 7 wascompletely free of any amine odor.

EXAMPLES 18 and 19

In accordance with these examples, 3-(N-morpholino)-N',N'-dimethylpropionamide andN,N'-piperazino-bis[3-(N",N"-dimethylpropionamide) ], designated hereinas Amine Catalysts VI and VII, were employed as the respective soleamine catalysts of a reaction mixture (foam Formulation D) whichotherwise contains components employed commercially for the manufactureof free-rise (slabstock) flexible polyurethane foam. The foams wereprepared following Foam Procedure II. The composition of FoamFormulation D and the results are given in Table VII which follows.

                  TABLE VII                                                       ______________________________________                                        Example No.            18       19                                            Foam No.               8        9                                             Foam Formulation D, Parts By Weight                                           Polyol D: A glycerol-started poly(oxy-                                                               100      100                                           propylene) triol having a Hydroxyl No.                                        of about 56.                                                                  Polyisocyanate B: A mixture of the 2,4-                                                              49.75    49.75                                         and 2,6- isomers of tolylene diiso-                                           cyanate present in a weight ratio of                                          80:20, respectively. (Index = 105)                                            Water                  4        4                                             Stannous octoate       0.275    0.30                                          Surfactant D /1/       1.0      1.0                                           Amine Catalysts:                                                              Amine Catalyst VI /2/  0.40     --                                            Amine Catalyst VII /3/ --       0.40                                          Cream Time, seconds    13       13                                            Rise Time, seconds     111      110                                           Foam Properties                                                               Resiliency, % ball rebound                                                                           41       42                                            Porosity, ft..sup.3 /min./ft..sup.2                                                                  84       65.5                                          Density, lbs./ft..sup.3                                                                              1.79     1.71                                          ILD (4"), lbs./50 in..sup.2                                                    25% deflection        37.0     38.0                                           65% deflection        80.0     73.5                                           25% return            25.4     23.9                                           Return value, %       68.7     62.9                                          Load Ratio             2.16     1.94                                          Compression Sets, %                                                            90%                   5.11     5.28                                           50% After Humid Aging /4/                                                                           7.17     7.6                                           Tensile strength, p.s.i.                                                                             16.7     15.2                                          Elongation, %          217      202                                           Tear Resistance, lbs./in.                                                                            2.47     2.34                                          Humid Age Load Loss, % /4/                                                                           15.4     12.9                                          ______________________________________                                         /1/ A polyoxyalkylene-polysiloxane block copolymer having the average         composition: MeSi[(OSiMe.sub.2).sub.6.4 (OC.sub.2 H.sub.4).sub.19             (OC.sub.3 H.sub.6).sub.14 OC.sub.4 H.sub.9 ].sub.3 wherein Me is methyl.      /2/ 3-(N-Morpholino)-N',N'-dimethylpropionamide.                              /3/ N,N'-Piperazino-bis[3-(N",N"-dimethylpropionamide)].                      /4/ Five hours at 120° C. in 100% relative humidity.              

The data of Table VII demonstrate that Amine Catalysts VI and VII arecatalytically active in promoting the isocyanate-water reaction, asreflected by rise time and the highly porous nature of the foamproducts. The data also indicate the efficacy of these catalysts inallowing for the formation of flexible foams having a good combinationof physical properties including low compression set values and low loadlosses after humid aging. These foams were also completely odorless.

EXAMPLES 20-23

In accordance with these examples, 3-dimethylamino-N,N-dimethylpropionamide (Amine Catalyst I) and 2-(N,N-dimethylamino)ethyl3-dimethylaminopropionate (Amine Catalyst X) were employed as therespective sole amine catalysts of Foam Formulation D (Table VII) inplace of Amine Catalysts VI and VII. The foams were prepared followingfree-rise Foam Procedure II. The concentration of amine catalyst andstannous octoate employed in these examples and the results are given inTable VIII which follows.

                  TABLE VIII                                                      ______________________________________                                        FLEXIBLE FOAMS (Free-Rise)                                                    ______________________________________                                        Example No.        20     21      22   23                                     Foam No.           10     11      12   13                                     Foam Formulation D /1/                                                         Stannous octoate, p.p.h.p.                                                                      0.3    0.425   0.25 0.275                                   Amine Catalyst I /2/, p.p.h.p.                                                                  0.1    0.20    --   --                                      Amine Catalyst X /3/, p.p.h.p.                                                                  --     --      0.40 0.20                                   Cream Time, seconds                                                                              11     11      12   13                                     Rise Time, seconds 90     70      100  103                                    Foam Properties                                                                Resiliency, % ball rebound                                                                      45     44      45   46                                      Porosity, ft..sup.3 /min./ft..sup.2                                                             97     61      93   93.5                                    Density, lbs./ft..sup.3                                                                         1.62   1.55    1.56 1.62                                    ILD (4"), lbs./50 in..sup.2                                                    25% deflection   38.5   38.5    33.0 40.9                                     65% deflection   70     65.8    58.4 76.1                                     25% return       26.7   26.4    21.4 26.2                                     Return value, %  69.4   68.6    64.9 64.0                                    Load Ratio        1.82   1.71    1.77 1.86                                    Compression Sets, %                                                            75%              4.1    4.6     --   --                                       90%              --     --      7.32 5.15                                    Tensile strength, p.s.i.                                                                        17.3   19.3    15.4 15.2                                    Elongation, %     204    232     215  173                                     Tear Resistance, lbs./in.                                                                       2.63   2.72    2.43 2.07                                    Humid Age Load Loss, % /4/                                                                      6.8    8.17    9.18 14.7                                   ______________________________________                                         /1/ Except for the variation in stannous octoate concentration and the        amine catalyst employed, the composition of this formulation is as define     in Table VII.                                                                 /2/ 3-Dimethylamino-N,N-dimethylpropionamide.                                 /3/ 2-(N,N-dimethylamino)ethyl 3-dimethylaminopropionate.                     /4/ Aged five hours at 120° C. in 100% relative humidity.         

The results of Table VIII further indicate that the catalysts describedherein are effective promoters of the water-isocyanate reaction and, asreflected by the relatively short rise time, Amine Catalyst I hasparticularly good reactivity in this respect. The data also indicatethat the flexible foam products were highly porous and had a goodoverall combination of properties. For the purpose of comparison, it isnoted that when 0.1 p.p.h.p. of a 70 weight per cent solution ofbis[2-(N,N-dimethylamino)ethyl]ether (i.e., Amine Catalyst A) isemployed as the sole amine catalyst of Foam Formulation D at the samestannous octoate level (0.30 p.p.h.p.) employed in Example 20, theresulting formulation provides a cream time of 10 seconds and a risetime of 80 seconds, and the flexible foam product has the followingproperties (expressed on the basis of the same units shown in TableVIII): porosity = 58.7; resiliency = 46; density = 1.45; 25% ILD = 39.1;load ratio = 1.72; 90% compression set = 3.36; tensile strength = 17.4;elongation = 235; and humid age load loss = 14.1.

EXAMPLES 24-30

A series of free-rise, flexible foams was prepared employing reactionmixtures containing the beta-amino carbonyl catalysts of the inventionin combination with bis[2-(N,N-dimethylamino)ethyl]ether. The particularbeta-amino carbonyl compounds employed were Amine Catalysts I-V, VIIIand IX, respectively. The composition of the reaction mixtures,designated Foam Formulation E, is given in Table IX.

                  TABLE IX                                                        ______________________________________                                        FOAM FORMULATION E                                                                                Parts By Weight                                                                 Control  Examples                                          Component          K-4      24-30                                          ______________________________________                                        Polyol E: A polyether triol having a                                                                100      100                                            Hydroxyl No. of 46 and containing less                                        than 5 mole per cent of primary hydroxyl                                      groups, derived from glycerol, propylene                                      oxide and ethylene oxide, about 14                                            weight per cent of total oxide being                                          ethylene oxide.                                                               Polyisocyanate B: An 80:20 mixture of                                                               48.2     48.2                                           the 2,4- and 2,6- isomers of tolylene                                         diisocyanate, respectively. (Index = 105)                                     Water                 4.0      4.0                                            Stannous octoate       0.25     0.25                                          Surfactant D /1/      1.0      1.0                                            Amine Catalysts                                                               Amine Catalyst A: A 70 weight per cent                                                              0.1      --                                             solution of bis[2-(N,N-dimethylamino)-                                        ethyl]ether in dipropylene glycol.                                            Blend: A 67/33 parts by weight blend                                                                --       0.1                                            of Amine Catalysts I-V, VIII or IX                                            and bis[2-(N,N-dimethylamino)ethyl]-                                          ether.                                                                        ______________________________________                                         /1/ As defined in Table VII.                                             

As indicated in Table IX, the catalysts employed in the examples wereadded as blends (0.1 part) containing 67 and 33 parts by weight of thebeta-amino carbonyl compound and bisether, respectively, therebyproviding 0.067 and 0.033 part by weight of each type of catalyst per100 parts of polyol reactant (p.p.h.p.). As further indicated in TableIX, the control formulation employed in Control Run K-4, contained thebisether (0.070 p.p.h.p.) as the sole amine catalyst, added as 0.1 partof a 70 weight per cent solution thereof. The various foams wereprepared following Foam Procedure II. The results are given in Table X.

                                      TABLE X                                     __________________________________________________________________________    Example No.              --   24   25  26   27   28  29   30                  Control Run No.          K-4  --   --  --   --   --  --   --                  Foam No.                 K-4  14   15  16   17   18  19   20                  Foam Formulation E /1/                                                         Amine Catalyst No.      --   I    II  III  IV   V   VIII IX                   Parts By Weight p.h.p.  None 0.067                                                                              0.067                                                                             0.067                                                                              0.067                                                                              0.067                                                                             0.067                                                                              0.067                Bis[2-(N,N-dimethylamino)ethyl]ether, p.p.h.p.                                                        0.070                                                                              0.033                                                                              0.033                                                                             0.033                                                                              0.033                                                                              0.033                                                                             0.033                                                                              0.033               Cream Time, seconds      9    10   9   10   9    9   9    11                  Rise Time, seconds       78   94   82  80   78   78  90   90                  Foam Properties                                                               Resiliency, % ball rebound                                                                             45   44   42  44   47   43  42   42                  Porosity, ft..sup.3 /min./ft..sup.2                                                                    55.5 107.5                                                                              73.6                                                                              75.8 73.6 75.8                                                                              90.4 97.4                Density, lbs./ft..sup.3  1.53 1.60 1.61                                                                              1.56 1.59 1.62                                                                              1.63 1.66                ILD (4"), lbs./50 in..sup.2                                                    25% deflection          39.1 38.6 37.8                                                                              38.4 36.2 36.0                                                                              42.8 41.7                 65% deflection          66.0 66.8 69.9                                                                              69.5 66.9 67.4                                                                              73.2 73.4                 25% return              24.7 24.6 24.5                                                                              24.1 24.0 23.9                                                                              26.3 25.8                 Return value, %         63.2 63.7 64.8                                                                              63.5 66.3 66.4                                                                              61.4 61.9                Load Ratio               1.69 1.73 1.85                                                                              1.81 1.84 1.87                                                                              1.71 1.76                Compression Sets, %                                                            90%                     5.50 5.51 7.33                                                                              7.14 8.13 6.95                                                                              4.66 5.12                 50% After Humid Aging /2/                                                                             6.23 6.56 11.1                                                                              10.6 11.8 11.3                                                                              6.02 5.94                Tensile strength, p.s.i. 20.0 17.4 18.3                                                                              18.5 19.4 19.1                                                                              17.20                                                                              17.1                Elongation, %            273  248  279 292  290  284 233  245                 Tear Resistance, lbs./in.                                                                              3.14 3.02 4.20                                                                              3.58 3.61 3.60                                                                              3.47 3.02                Humid Aged Load Loss, % /2/                                                                            24.8 20.2 16.6                                                                              14.8 14.5 15.8                                                                              18.7 18.5                __________________________________________________________________________     /1/ As defined in Table IX.                                                   /2/ After aging for five hours at 120° C. in 100% relative             humidity.                                                                

The results of Table X indicate that the blended amine catalystsemployed in Examples 24-30 provided flexible foams having an overallgood combination of physical properties as compared with Control FoamK-4 and that certain individual properties were superior. Thus, in eachinstance, Foam Nos. 14-20 were markedly more porous than the controlfoam; particularly outstanding in this respect were Foam No. 14 based onAmine Catalyst I (3-dimethylamino-N,N-dimethylpropionamide), Foam No. 19based on Amine Catalyst VIII [ethyl 3-(N,N-dimethylamino)propionate],and Foam No. 20 based on Amine Catalyst IX [ethyl3-(N,N-diethylamino)propionate]. In addition to their enhanced porosity,Foam Nos. 14-20 also exhibited lower load loss values after humid agingthan the control foam; especially outstanding in this respect were FoamNos. 15-18 based on Amine Catalysts II-V, respectively. Of furthersignificance is the realization of these improvements without thenecessity of employing catalysts associated with the odor characteristicof amines; freshly prepared Foams 14-20 were odorless.

EXAMPLES 31-37

In accordance with these examples, another series of foams was preparedemploying respective reaction mixtures based on the blends of AmineCatalysts I-V, VIII and IX described under Examples 24-30. Thecomposition of the reaction mixtures (Foam Formulation F) including thatemployed in Control Run K-5 is given in Table XI.

                  TABLE XI                                                        ______________________________________                                        FOAM FORMULATION F                                                                               Parts By Weight                                                                 Control   Examples                                          Component         K-5       31-37                                          ______________________________________                                        Polyol E /1/         100       100                                            Polyisocyanate B /1/ (Index = 105)                                                                 37.9      37.9                                           Water                3.0       3.0                                            Stannous octoate      0.275     0.275                                         Surfactant E /2/     1.0       1.0                                            Amine Catalysts                                                               Amine Catalyst A: A 70 weight per                                                                  0.1       --                                              cent solution of bis[2-(N,N-                                                  dimethylamino)ethyl]ether in                                                  dipropylene glycol.                                                          Blend: A 67/33 parts by weight blend                                                               --        0.1                                             of Amine Catalysts I-V, VIII or IX                                            and bis[2-(N,N-dimethylamino)ethyl]-                                          ether.                                                                       ______________________________________                                         /1/ As defined in Table IX.                                                   /2/ A polysiloxane-polyoxyalkylene block copolymer having the average         composition Me.sub.3 SiO(Me.sub.2 SiO).sub.72 [MeO(C.sub.3 H.sub.6            O).sub.29 (C.sub.2 H.sub.4 O).sub.20 C.sub.3 H.sub.6 SiMeO].sub.5.1           SiMe.sub.3 where Me is methyl, employed as a 55 weight per cent active        solution.                                                                

The foams of these examples as well as the control foam were preparedfollowing Foam Procedure II. The results are given in Table XII.

                                      TABLE XII                                   __________________________________________________________________________    Example No.              --   31   32  33   34   35  36   37                  Control Run No.          K-5  --   --  --   --   --  --   --                  Foam No.                 K-5  21   22  23   24   25  26   27                  Foam Formulation F /1/                                                         Amine Catalyst No.      --   I    II  III  IV   V   VIII IX                   Parts By Weight p.h.p.  None 0.067                                                                              0.067                                                                             0.067                                                                              0.067                                                                              0.067                                                                             0.067                                                                              0.067                Bis[2-(N,N-dimethylamino)ethyl]ether, p.p.h.p.                                                        0.070                                                                              0.033                                                                              0.033                                                                             0.033                                                                              0.033                                                                              0.033                                                                             0.033                                                                              0.033               Cream Time, seconds      7    11   11  11   10   10  10   12                  Rise Time, seconds       95   118  106 106  100  101 120  128                 Foam Properties                                                               Resiliency, % ball rebound                                                                             46   49   44  43   45   46  29   29                  Porosity, ft..sup.3 /min./ft..sup.2                                                                    18.1 41.7 14.2                                                                              9.7  29.2 30.8                                                                              4.2  1.7                 Density, lbs./ft..sup.3  1.83 1.98 1.91                                                                              1.88 1.91 1.90                                                                              1.85 1.88                ILD (4"), lbs./50 in..sup.2                                                    25% deflection          34.6 40.0 37.0                                                                              35.6 34.6 34.0                                                                              45.0 45.4                 65% deflection          62.0 71.4 66.8                                                                              66.4 63.5 62.4                                                                              77.4 78.0                 25% deflection          24.0 27.8 25.1                                                                              24.4 24.0 23.6                                                                              30.3 30.5                 Return value, %         69.4 69.4 67.8                                                                              68.5 69.4 69.4                                                                              67.3 67.2                Load Ratio               1.79 1.79 1.81                                                                              1.87 1.85 1.84                                                                              1.72 1.72                Compression Sets, %                                                            90%                     6.62 4.73 6.73                                                                              6.28 5.67 5.44                                                                              6.00 5.07                 50% After Humid Aging /2/                                                                             6.92 4.95 8.87                                                                              8.70 8.11 7.64                                                                              5.52 5.86                Tensile strength, p.s.i. 17.2 15.6 19.5                                                                              18.8 18.1 19.6                                                                              15.90                                                                              16.4                Elongation, %            291  217  301 294  300  333 210  223                 Tear Resistance, lbs./in.                                                                              3.45 2.98 3.20                                                                              2.90 3.00 3.22                                                                              1.99 2.27                Humid Aged Load Loss, % /2/                                                                            26.8 24.6 16.73                                                                             20.7 19.1 20.0                                                                              22.4 24.9                __________________________________________________________________________     /1/ As defined in Table XI.                                                   /2/ After aging for five hours at 120° C. in 100% relative             humidity.                                                                

As indicated by data of Table XII and as recognized in its use, FoamFormulation F is a difficult reaction mixture to prepare as acommercially open, porous product. Thus it was not surprising thatControl Foam K-5, as well as Foam Nos. 22, 23, 26 and 27, had porosityvalues less than 20. On the other hand, it was unexpected to find thatunder this unfavorable condition, Foam Nos. 21, 24 and 25 based on AmineCatalysts I, IV and V, had acceptable open, porous structures asreflected by their respective porosity values of 41.7, 29.2 and 30.8.

EXAMPLES 38-46

The purpose of these examples is to illustrate the efficacy of thebeta-amino carbonyl compounds as catalytic components of flame-retardedfoam formulations (Examples 38-43) and their operating latitude withrespect to variation in concentration of tin cocatalyst in suchformulations as well as in non flame-retarded systems (Examples 44-46).The compositions of the reaction mixtures are given in Table XIII. InExamples 38-45, the amine catalysts were added to the formulation as an80:20 parts by weight blend of Amine Catalyst I andbis[2-(N,N-dimethylamino)ethyl]ether, respectively. A 67/33 parts byweight blend of these catalysts was used in Example 46. Based on 100parts of polyol inclusive of flame-retardant when present, either 0.1 or0.2 part of the respective blends were used. The foams were formedfollowing Foam Procedure II. The results are given in Table XIII wherein"SE" indicates that the foam sample qualified for a self-extinguishingrating under flammability test ASTM D-1692-67T. Table XIII also includesdata, as Runs A and B, by way of illustrating a common effect thatflame-retardants often have on flexible foam porosity.

                                      TABLE XIII                                  __________________________________________________________________________    Example No.        -- --  38 39  40  41   42  43   44  45  46                 Run No             A  B   -- --  --  --   --  --   --  --  --                 Foam No.           A  B   28 29  30  31   32  33   34  35  36                 Formulation, Parts By Weight                                                  Polyol D /1/       90 90  90 90  90  90   90  90   100 100 100                Dibromoneopentyl glycol                                                                          10 10  10 10  --  5    5   5    --  --  --                 Tribromoneopentyl alcohol                                                                        -- --  -- --  10  5    5   5    --  --  --                 Polyisocyanate B /1/ (Index = 105)                                                               55.8                                                                             55.8                                                                              55.8                                                                             55.8                                                                              51.63                                                                             53.72                                                                              53.72                                                                             53.72                                                                              49.7                                                                              49.7                                                                              49.7               Water              4.0                                                                              4.0 4.0                                                                              4.0 4.0 4.0  4.0 4.0  4.0 4.0 4.0                Stannous octoate   0.10                                                                             0.10                                                                              0.10                                                                             0.10                                                                              0.275                                                                             0.175                                                                              0.20                                                                              0.20 0.325                                                                             0.40                                                                              0.35               Surfactant D /1/   1.0                                                                              1.0 -- --  --  --   --  --   --  --  1.0                Surfactant F /2/   -- --  0.45                                                                             0.45                                                                              0.45                                                                              0.45 0.45                                                                              0.45 0.45                                                                              0.45                                                                              --                 Bis[2-(N,N-dimethylamino)ethyl]ether                                                             0.07                                                                             0.03                                                                              0.02                                                                             0.04                                                                              0.04                                                                              0.04 0.04                                                                              0.02 0.02                                                                              0.04                                                                              0.033              Amine Catalyst I   -- --  0.08                                                                             0.16                                                                              0.16                                                                              0.16 0.16                                                                              0.08 0.08                                                                              0.16                                                                              0.067              Cream Time, seconds                                                                              7  7   13 11  11  12   11  13   11  9   12                 Rise Time, seconds 89 101 135                                                                              112 81  92   87  101  85  68  95                 Foam Properties                                                               Resiliency, % hall rebound                                                                              36 37  38  37   33  34   45  45  44                 Porosity, ft..sup.3 /min./ft..sup.2                                                              C  C   73 60  90  80.6 61.3                                                                              42.3 68.7                                                                              61.6                                                                              80.7               Density, lbs./ft..sup.3                                                                          L  L   1.47                                                                             1.47                                                                              1.43                                                                              1.43 1.40                                                                              1.42 1.46                                                                              1.45                                                                              1.58               ILD (4"), lbs. 50/in..sup.2                                                                      O  O                                                        25% deflection    S  S   34.2                                                                             29.6                                                                              32.1                                                                              34.1 36.0                                                                              38.1 33.4                                                                              35.0                                                                              40.2                65% deflection    E  E   63.6                                                                             56.4                                                                              55.2                                                                              59.8 65.1                                                                              68.5 61.0                                                                              61.8                                                                              74.0                25% return        D  D   19.8                                                                             17.4                                                                              17.8                                                                              19.3 20.4                                                                              20.9 21.0                                                                              22.1                                                                              25.2                Return value, %          57.8                                                                             58.7                                                                              55.4                                                                              56.6 56.7                                                                              54.8 62.8                                                                              63.2                                                                              62.7                Load Ratio               1.86                                                                             1.91                                                                              1.72                                                                              1.75 1.81                                                                              1.80 1.83                                                                              1.77                                                                              1.84               90% Compression Set, %    23.6                                                                             36.3                                                                              13.9                                                                              90.6 21.4                                                                              25.8 7.12                                                                              6.97                                                                              5.69               50% Compression Set, % /3/                                                                       F  F   65.2                                                                             67.3                                                                              12.5                                                                              27.4 41.5                                                                              53.6 9.20                                                                              9.12                                                                              5.68               Tensle strength, p.s.i.                                                                          O  O   18.7                                                                             19.6                                                                              15.8                                                                              18.9 16.9                                                                              18.2 16.5                                                                              17.0                                                                              16.0               Elongation, %      A  A   195                                                                              215 231 236  232 240  240 237 215                Tear Resistance, lbs./in.                                                                        M  M   3.06                                                                             2.98                                                                              2.71                                                                              2.90 2.96                                                                              2.96 2.58                                                                              2.72                                                                              2.33               Humid Age Load Loss, % /3/                                                                              12.9                                                                             6.85                                                                              7.24                                                                              11.9 6.68                                                                              5.70 9.22                                                                              6.69                                                                              16.5               Flammability (ASTM D-1692-67)                                                  Extinguishing time, seconds                                                                            17 17  31.4                                                                              23.1                                      Burning extent, inches   1.50                                                                             1.56                                                                              2.41                                                                              1.88                                      Burning rate, in./min.   5.1                                                                              5.33                                                                              4.62                                                                              4.89                                      Flame-rating             SE SE  SE  SE                                       __________________________________________________________________________     /1/ As defined in Table VII.                                                  /2/ A polysiloxane-polyoxyalkylene block copolymer having the average         composition, Me.sub.3 SiO(Me.sub.2 SiO).sub.60 [NC(CH.sub.2).sub.3            SiMeO].sub.10 [MeO(C.sub.3 H.sub.6 O).sub.30 (C.sub.2 H.sub.4 O).sub.26.4     C.sub.3 H.sub.6 SiMeO].sub.6 SiMe.sub.3 where Me is methyl.                   /3/ After aging for 5 hours at 120° F. in 100% relative humidity. 

The results of Examples 38-43 indicate that the present discovery ofamine urethane catalysts which are capable of providing very highporosity polyurethane foam is of particular value in the preparation ofhighly porous, flame-retarded foams. The more usual result isillustrated by Run Nos. A and B wherein the inclusion of the reactiveflame-retardant, dibromoneopentyl glycol, provided foams that shrankcompletely. It should be understood that the excellent flammabilityproperties of the foams produced in Examples 38-43 is in large measureattributable to the particular cyanopropylmodified silicone surfactant(Surfactant F) employed. Thus, when the beta-amino carbonyl catalysts ofthis invention are employed in combination with this surfactant,particularly effective formulations are provided for preparing open,highly porous flexible foams having excellent flame-retardant character.The data of Table XIII also show that these desirable results arerealized under a variety of conditions and that increasing the tinco-catalyst (stannous octoate) levels to up-grade foam physicalproperties can be accomodated and still retain foam processability.

The versatility of the beta-amino carbonyl compounds as effectivecatalytic components of a wide variety of reaction mixtures is furtherdemonstrated by the following Examples 47 and 48 drawn to thepreparation of rigid polyurethane foams. In preparing these foams, allcomponents except the polyisocyanate reactant were mixed for 15 secondsand, after appropriate adjustment for loss of fluorocarbon blowingagent, mixing was continued for an additional 15 seconds. The organicpolyisocyanate was then added and, after mixing the complete formulationfor 5 seconds, it was poured into an open box (12" × 12" × 12"). Risewas measured until the rate of rise was less than one millimeter per 10seconds.

EXAMPLE 47

The rigid foam formulation employed in this example contained (on aweight basis): (a) 100 parts of a sucrose-based polyol having a hydroxylnumber of about 400 prepared as a mixed adduct of sucrose,diethylenetriamine and aniline; (b) 108 parts of a tolylene diisocyanateproduced as a residue product in the manufacture of the 2,4- and 2,6-isomers of tolylene diisocyanate and having a free -NCO content of about38.5 weight per cent (Index - 108); (c) 1.6 parts of water; (d) 44 partsof inhibited trichlorofluorofluoromethane blowing agent; (e) 1.5 partsof a tin catalyst; and (f) 2 parts of3-dimethylamino-N,N-dimethylpropionamide (Amine Catalyst I). For thepurpose of comparison, a control formulation was employed containing theaforesaid components (a)-(e) and, as amine catalyst component (f), 2parts of dimethylethanolamine in place of Amine Catalyst I. Formulationreactivity is indicated by the following results, the values withinparenthesis applying to the control formulation: Cream time= 10 (8)seconds; Gel time = 25 (35) seconds; Tack-free time = 35 (50) seconds;and Rise time = 35 (55) seconds. The lower gel, tack-free and rise timesindicate that the formulation containing Amine Catalyst I was the morereactive formulation. In both instances rigid foams of satisfactoryquality were obtained.

EXAMPLE 48

In accordance with this example, a rigid foam was prepared employing thefollowing components (on a weight basis): (a) 85 parts of asorbitol-based polyol having a Hydroxyl No. of about 490 and a molecularweight of about 700, derived from sorbitol, dipropylene glycol andpropylene oxide; (b) 13 parts of an amine pentol having a Hydroxyl No.of about 700, derived from diethylenetriamine and propylene oxide; (c) 2parts of glycerol; (d) 148 parts of a polyphenylmethylene polyisocyanatehaving an average -NCO functionality of 2.7 and a free --NCO content of30.5-32.3 weight per cent (Index = 115); (e) 41 parts oftrichlorofluoromethane blowing agent; (f) 4.2 parts of flame-retardant[0,0-diethyl-N, N-bis(2-hydroxyethyl)aminomethyl phosphonate]; (g) 1.6parts of surfactant (Union Carbide Corporation Silicone SurfactantL-5420); (h) 0.4 part of N,N,N',N'-tetramethylbutanediamine; and (i) 1.2parts of 3-dimethylamino-N, N-dimethylpropionamide (Amine Catalyst I).For the purpose of comparison, a control foam was prepared employing theabove formulation except that in place of Amine Catalyst I, 1.2 parts ofAmine Catalyst B was used (that is, a 33 weight per cent solution oftriethylenediamine in dipropylene glycol). Formulation reactivity was asfollows wherein corresponding data for the control are given inparenthesis: Cream time = 60 (35) seconds; Gel time = 100 (85) seconds;Tack-free time = 190 (110) seconds; Rise time = 200 (130) seconds. Thesedata show that, although reactivity of the control formulation washigher, Amine Catalyst I provided satisfactory results in this respect.In both instances, rigid foams of satisfactory quality were obtained.

What is claimed is:
 1. 3-Diethylamino-N,N-dimethylpropionamide. 2.3-Dimethylamino-N,N-dimethylbutyramide which has the formula, ##STR21##